Please provide notes on pacemaker troubleshooting

Reading File

Finding Sources

Searching PubMed

"pacemaker" AND "troubleshooting" AND "malfunction"

Reading File

Loading Image

I now have comprehensive material from three authoritative textbooks. Here are detailed notes on pacemaker troubleshooting:

Pacemaker Troubleshooting

Sources: Braunwald's Heart Disease (9780323722193), Rosen's Emergency Medicine (9780323757898), Tintinalli's Emergency Medicine (9781260019933)

Initial Evaluation Approach

A multimodality approach is required for all suspected pacemaker dysfunction:

Telemetry and multichannel ECG
Device programmer interrogation (battery level, lead integrity, stored data, programmed parameters)
Chest radiograph (lead position, lead fracture, number of leads)
Knowledge of active device algorithms and programmed parameters
External environment assessment — sources of electromagnetic interference (EMI)
Provocative maneuvers — pocket manipulation, arm movement
Magnet application — converts pacemaker to fixed-rate (asynchronous) mode by closing the reed switch; allows assessment of pacing rate and capture when the native rate exceeds the programmed rate

Symptomatic malfunction after implantation occurs in < 5% of patients and is rarely life-threatening. The most common cause is inappropriate sensing, followed by failure to capture.

The Four Categories of Pacemaker Malfunction

1. Failure to Capture

Definition: Pacing stimulus delivered but fails to depolarize the myocardium. May be complete or intermittent.

ECG findings: Pacemaker spikes not followed by a paced QRS complex (or P wave). In complete absence of spikes, consider battery depletion or lead fracture.

Causes:

Cause	Notes
Lead dislodgement	Most common cause; most likely in first month post-implant
Lead fracture / insulation break	Occurs at stress points — attachment to pulse generator or abrupt angulations; current leakage detected on interrogation
Lead–header connection problem	Inadequate contact between lead and generator header
Output programmed below threshold	Pacing output < capture threshold
Exit block	Adequate stimulus fails to capture due to endocardial changes — ischemia/infarction, hyperkalemia, class III antiarrhythmics (e.g., amiodarone)
Battery depletion	Gradual decline; output eventually falls below threshold
Functional failure to capture	Pacing spike falls within refractory period (physiologic, from undersensing) — not true malfunction

Note: Auto-threshold algorithms in modern devices can detect and compensate for threshold elevation by automatically adjusting output.

2. Failure to Pace (Oversensing)

Definition: The pulse generator is inhibited and does not deliver a stimulus when it should. Oversensing is the primary cause.

ECG findings: Pauses or bradycardia; absent expected pacing spikes.

Causes of oversensing:

Myopotentials — pectoralis muscle signals (especially with unipolar leads)
T-wave oversensing — most common over-sensed cardiac signal following intrinsic ventricular depolarization
Electromagnetic interference (EMI): electrocautery (can cause temporary inhibition), diaphragm, nerve stimulators, broken leads
Lead conductor fracture — generates noise that is sensed as cardiac activity
MRI — can alter circuitry and force fixed-rate/asynchronous pacing (many modern devices are MRI-conditional)
Crosstalk — ventricular channel sensing the atrial pacing stimulus

Management: If corrected by magnet (asynchronous mode) → oversensing or algorithmic cause; if not corrected → pulse generator failure or lead conductor fracture.

3. Failure to Sense (Undersensing)

Definition: The pacemaker fails to detect intrinsic cardiac electrical activity and fires inappropriately.

ECG findings: Pacing spikes occur earlier than expected in the cycle (inappropriate timing). The spike may or may not capture, depending on whether it falls within the refractory period.

Causes:

Lead displacement, fracture, or poor endocardial contact
Low-amplitude intracardiac signals (RV infarction, cardiomyopathy with fibrosis)
Sensing threshold programmed too high
Sensing circuit failure

A spike falling during the ventricular refractory period that does not produce a complex is not failure to pace — it is a normal consequence of undersensing.

4. Inappropriate Pacing Rate

A. Rate Lower Than Programmed

Battery depletion — gradual decrease in pacing rate is typically the first sign of voltage depletion in lithium-iodine batteries (does not occur suddenly)
Upper rate behavior — if sinus rate exceeds upper tracking rate in AV block, pacing rate drops; can manifest as a Wenckebach-like pattern or 2:1 block behavior
Oversensing — prolonged escape interval

B. Rate Higher Than Programmed (Rapid Pacing)

Cause	Mechanism
Pacemaker-mediated tachycardia (PMT)	PVC → retrograde VA conduction → atrial depolarization outside PVARP → tracked by device → VP → cycle repeats ("endless loop")
Tracking atrial arrhythmias	Atrial flutter/fibrillation waves sensed and tracked at upper rate limit (prevented by mode switch)
Runaway pacemaker	Rate above upper limit; rare; battery failure or external interference; magnet application may terminate
Sensor-driven pacing	Rate-responsive sensor (e.g., accelerometer) drives rate inappropriately
Rate smoothing algorithms	Designed to prevent abrupt rate changes

Treatment of PMT: Magnet application converts to fixed rate and breaks the endless loop. Device interrogation and PVARP extension prevents recurrence.

ECG tracings showing pacemaker malfunctions: A=undersensing, B=oversensing, C=failure to capture

ECG tracings of pacemaker malfunctions — A: Undersensing; B: Oversensing; C: Failure to capture (Tintinalli's)

Special Considerations

Exit Block

Failure of an adequate stimulus to depolarize the paced chamber despite a functional generator and intact lead. Causes:

Ischemia/infarction of endocardium at electrode contact
Systemic hyperkalemia
Class III antiarrhythmics (amiodarone)

Pacing-Induced Proarrhythmia

R-on-T pacing in VOO mode → VT/VF
Ventricular or atrial undersensing → competitive pacing → arrhythmia trigger
Short-long-short sequences (e.g., during threshold testing or RV pacing-minimization) → VT/VF
Competitive atrial pacing → atrial tachyarrhythmias

Pseudo-Malfunction

Many apparent abnormalities represent normal device function:

Bipolar pacing spikes may be invisible depending on lead vector
Automatic threshold tests with loss of capture may appear abnormal on monitor
AV search algorithms cause variable AV intervals
Mode switch, RV pacing minimization algorithms

Diagnostic Workup Summary

Test	Purpose
Chest radiograph	Lead tip position, fracture, number of leads, lead–generator connection
12-lead ECG + rhythm strip	Pattern of malfunction (sensing vs. capture vs. rate)
Device interrogation	Battery status, lead impedances, pacing/sensing thresholds, stored electrograms, active algorithms
Magnet application	Converts to asynchronous mode → assesses capture; terminates PMT/runaway pacemaker

A ventricular lead tip in the RVOT or atrial lead in the SVC or RV on CXR is always abnormal.

Causes Summary Box (Rosen's)

Problem	Causes
Failure to capture	Lead disconnection/break/displacement, exit block, battery depletion
Undersensing	Lead displacement, inadequate endocardial contact, low-voltage P/QRS, lead fracture
Oversensing	Extracardiac signals (myopotentials), T-wave sensing
Inappropriate rate	Battery depletion, VA conduction with PMT, 1:1 response to atrial arrhythmias

Braunwald's Heart Disease, p. 603–607 | Rosen's Emergency Medicine, p. 1075–1076 | Tintinalli's Emergency Medicine, p. 263

Please make ppt on subcutaneous icd

Reading File

Finding Sources

Reading File

Finding Sources

Reading File

Searching Images

subcutaneous ICD device implant anatomy lead position

Running Command

node /home/daytona/skills/shared/scripts/fetch_images.js \ "https://cdn.orris.…

Running Command

mkdir -p /home/daytona/workspace/sicd-ppt && node /home/daytona/skills/shared/sc…

Writing File

~/sicd-ppt/build.js

const pptxgen = require("pptxgenjs");
const fs = require("fs");

// Load images
const images = JSON.parse(fs.readFileSync("/home/daytona/workspace/sicd-ppt/images.json"));
const img0 = images[0].base64; // CXR showing S-ICD placement
const img1 = images[1].base64; // Lateral CXR S-ICD
const img2 = images[2].base64; // Braunwald comparison diagram

const pres = new pptxgen();
pres.layout = "LAYOUT_16x9";
pres.title = "Subcutaneous ICD (S-ICD)";
pres.author = "Orris Medical";

// ─── Color palette ───────────────────────────────────────────
const NAVY   = "0A1F44";   // dominant dark background
const TEAL   = "00A8A8";   // accent / highlights
const WHITE  = "FFFFFF";
const LIGHT  = "D6EAF8";   // soft highlight
const GRAY   = "B0BEC5";
const AMBER  = "FFC107";   // warning / caution callouts

// ─── Reusable helpers ────────────────────────────────────────
function addHeader(slide, title, subtitle) {
  // dark header band
  slide.addShape(pres.shapes.RECTANGLE, {
    x: 0, y: 0, w: 10, h: 1.2,
    fill: { color: NAVY },
    line: { color: NAVY }
  });
  slide.addText(title, {
    x: 0.3, y: 0.1, w: 9.4, h: 0.7,
    fontSize: 26, bold: true, color: WHITE, fontFace: "Calibri", margin: 0
  });
  if (subtitle) {
    slide.addText(subtitle, {
      x: 0.3, y: 0.78, w: 9.4, h: 0.38,
      fontSize: 13, color: TEAL, fontFace: "Calibri", italic: true, margin: 0
    });
  }
  // teal accent line
  slide.addShape(pres.shapes.RECTANGLE, {
    x: 0, y: 1.2, w: 10, h: 0.07,
    fill: { color: TEAL }, line: { color: TEAL }
  });
}

function bullet(text, level) {
  return { text, options: { bullet: { indent: 15 }, indentLevel: level || 0, breakLine: true, fontSize: 14, color: "1A1A2E", fontFace: "Calibri" } };
}
function bulletBold(text) {
  return { text, options: { bullet: { indent: 15 }, bold: true, breakLine: true, fontSize: 14, color: NAVY, fontFace: "Calibri" } };
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 1 – Title                                         ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  // full background
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: NAVY }, line: { color: NAVY } });
  // teal band on left
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 0.18, h: 5.625, fill: { color: TEAL }, line: { color: TEAL } });
  // decorative circle
  s.addShape(pres.shapes.OVAL, { x: 6.8, y: 0.2, w: 3.5, h: 3.5, fill: { color: "0D2B5E", transparency: 30 }, line: { color: TEAL, pt: 2 } });

  s.addText("Subcutaneous ICD", {
    x: 0.5, y: 1.1, w: 6.8, h: 1.3,
    fontSize: 40, bold: true, color: WHITE, fontFace: "Calibri", margin: 0
  });
  s.addText("S-ICD", {
    x: 0.5, y: 2.35, w: 4, h: 0.7,
    fontSize: 30, bold: true, color: TEAL, fontFace: "Calibri", margin: 0
  });
  s.addText("A Comprehensive Clinical Overview", {
    x: 0.5, y: 3.0, w: 6.5, h: 0.5,
    fontSize: 17, color: GRAY, fontFace: "Calibri", italic: true, margin: 0
  });
  s.addText("Cardiology · Electrophysiology", {
    x: 0.5, y: 4.9, w: 6, h: 0.4,
    fontSize: 12, color: GRAY, fontFace: "Calibri", margin: 0
  });

  // embed CXR image in the circle area
  s.addImage({ data: img0, x: 7.0, y: 0.4, w: 2.8, h: 3.0, rounding: true });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 2 – What is the S-ICD?                            ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "What is the S-ICD?", "Entirely subcutaneous — no transvenous leads");

  // Left text column
  s.addText([
    bulletBold("Definition"),
    bullet("A fully subcutaneous implantable cardioverter-defibrillator — no intravascular or intracardiac leads", 1),
    bullet("Generator placed in left lateral subcutaneous tissue", 1),
    bullet("Single lead tunneled along left parasternal border", 1),
    { text: "", options: { breakLine: true } },
    bulletBold("Key Components"),
    bullet("Pulse generator (PG): larger than transvenous ICD — houses bigger battery + capacitors", 1),
    bullet("Subcutaneous sensing/defibrillation lead with 3 sensing electrodes", 1),
    { text: "", options: { breakLine: true } },
    bulletBold("Primary Function"),
    bullet("Detects and terminates ventricular tachycardia (VT) and ventricular fibrillation (VF)", 1),
    bullet("Delivers up to 80 J defibrillation shocks subcutaneously", 1),
    bullet("Does NOT provide ATP, resynchronization, or chronic bradycardia pacing", 1),
  ], { x: 0.3, y: 1.4, w: 5.6, h: 4.0, valign: "top" });

  // Image right side
  s.addImage({ data: img1, x: 6.0, y: 1.4, w: 3.7, h: 3.6 });
  s.addText("Lateral CXR — S-ICD generator & parasternal lead", {
    x: 5.9, y: 5.0, w: 4.0, h: 0.4,
    fontSize: 9, color: GRAY, italic: true, fontFace: "Calibri"
  });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 3 – Anatomy & Implant Position                    ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "Anatomy & Implant Position", "Key anatomical landmarks for S-ICD placement");

  s.addImage({ data: img0, x: 0.3, y: 1.4, w: 4.3, h: 3.8 });
  s.addText("PA CXR: Generator in left mid-axillary region;\nlead ascending along left parasternal border (arrows)", {
    x: 0.3, y: 5.2, w: 4.3, h: 0.3, fontSize: 9, color: GRAY, italic: true, fontFace: "Calibri"
  });

  // Right side info boxes
  const boxes = [
    { label: "Generator", text: "Subcutaneous pocket, left mid-axillary line, 5th–6th intercostal space", y: 1.5 },
    { label: "Lead", text: "Tunneled subcutaneously → xiphoid → ascending parasternal border toward manubrium", y: 2.5 },
    { label: "Sensing Electrodes", text: "3 electrodes: distal tip, proximal ring, device can — form 2 sensing vectors", y: 3.5 },
    { label: "Screening", text: "Pre-implant ECG screening required to assess T-wave oversensing & R-wave double-counting", y: 4.5 },
  ];
  boxes.forEach(b => {
    s.addShape(pres.shapes.ROUNDED_RECTANGLE, { x: 4.8, y: b.y, w: 4.9, h: 0.82, fill: { color: WHITE }, line: { color: TEAL, pt: 1.5 }, rectRadius: 0.08, shadow: { type: "outer", color: "000000", blur: 4, offset: 2, angle: 135, opacity: 0.1 } });
    s.addText([{ text: b.label + ": ", options: { bold: true, color: NAVY } }, { text: b.text, options: { color: "333333" } }], { x: 4.95, y: b.y + 0.07, w: 4.6, h: 0.68, fontSize: 12, fontFace: "Calibri", valign: "middle" });
  });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 4 – Indications                                   ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "Indications for S-ICD", "Patient selection criteria");

  // Green "ideal" column
  s.addShape(pres.shapes.RECTANGLE, { x: 0.3, y: 1.4, w: 4.3, h: 3.9, fill: { color: "E8F5E9" }, line: { color: "2E7D32", pt: 1.5 } });
  s.addText("✔  IDEAL CANDIDATES", { x: 0.4, y: 1.45, w: 4.1, h: 0.45, fontSize: 13, bold: true, color: "2E7D32", fontFace: "Calibri", margin: 0 });
  s.addText([
    bullet("No need for pacing (anti-tachycardia pacing [ATP], resynchronization, or bradycardia pacing)"),
    bullet("Young patients to avoid transvenous lead complications over lifetime"),
    bullet("Patients with limited venous access or congenital heart disease"),
    bullet("Prior device infection where new transvenous system is risky"),
    bullet("Channelopathies: Brugada syndrome, LQTS, HCM"),
    bullet("Hypertrophic cardiomyopathy (HCM)"),
    bullet("Patients at high risk of lead-related complications (e.g. dialysis patients)"),
  ], { x: 0.4, y: 1.9, w: 4.1, h: 3.3, valign: "top" });

  // Red "avoid" column
  s.addShape(pres.shapes.RECTANGLE, { x: 5.3, y: 1.4, w: 4.3, h: 3.9, fill: { color: "FFEBEE" }, line: { color: "C62828", pt: 1.5 } });
  s.addText("✘  AVOID / CONTRAINDICATIONS", { x: 5.4, y: 1.45, w: 4.1, h: 0.45, fontSize: 13, bold: true, color: "C62828", fontFace: "Calibri", margin: 0 });
  s.addText([
    bullet("Indication for anti-bradycardia pacing"),
    bullet("Indication for CRT (cardiac resynchronization therapy)"),
    bullet("Hemodynamically stable, pace-terminable VT requiring ATP"),
    bullet("Fails pre-implant ECG screening (7–10% of candidates)"),
    bullet("Patients needing His-bundle or LBB pacing"),
  ], { x: 5.4, y: 1.9, w: 4.1, h: 3.3, valign: "top" });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 5 – S-ICD vs Transvenous ICD Comparison          ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "S-ICD vs Transvenous ICD", "System selection comparison");

  // Table
  const rows = [
    [{ text: "Feature", options: { bold: true, color: WHITE } }, { text: "S-ICD", options: { bold: true, color: WHITE } }, { text: "Transvenous ICD", options: { bold: true, color: WHITE } }],
    ["Lead type", "Subcutaneous only", "Intravascular + intracardiac"],
    ["Pacing (bradycardia)", "No (30 s post-shock only)", "Yes"],
    ["Anti-tachycardia pacing (ATP)", "No", "Yes"],
    ["CRT capability", "No", "Yes"],
    ["MRI compatibility", "Conditional", "Conditional"],
    ["Lead extraction risk", "Lower — no intravascular lead", "Higher — vascular extraction risk"],
    ["Inappropriate shocks (yr 1)", "5–10%", "<2%"],
    ["Pocket infection rate", "~1.1%", "Higher"],
    ["Systemic infection", "Not reported", "Possible"],
    ["Battery longevity", "Shorter", "Longer"],
    ["Vascular access complications", "None (no venous access)", "Pneumothorax, cardiac perforation"],
  ];

  s.addTable(rows, {
    x: 0.3, y: 1.35, w: 9.4, h: 4.05,
    rowH: 0.32,
    fontSize: 11,
    fontFace: "Calibri",
    border: { pt: 0.5, color: "BDBDBD" },
    fill: "FFFFFF",
    color: "1A1A2E",
    align: "left",
    valign: "middle",
    colW: [2.2, 3.3, 3.9],
    autoPage: false,
  });

  // Override header row fill manually via first row styling
  // (pptxgenjs uses first row options from rows[0] cell options — just set fill on header row)
  // Add header row overlay
  s.addShape(pres.shapes.RECTANGLE, { x: 0.3, y: 1.35, w: 9.4, h: 0.32, fill: { color: NAVY }, line: { color: NAVY } });
  s.addText("Feature", { x: 0.35, y: 1.38, w: 2.1, h: 0.28, fontSize: 11, bold: true, color: WHITE, fontFace: "Calibri", margin: 0 });
  s.addText("S-ICD", { x: 2.55, y: 1.38, w: 3.2, h: 0.28, fontSize: 11, bold: true, color: TEAL, fontFace: "Calibri", align: "center", margin: 0 });
  s.addText("Transvenous ICD", { x: 5.85, y: 1.38, w: 3.8, h: 0.28, fontSize: 11, bold: true, color: AMBER, fontFace: "Calibri", align: "center", margin: 0 });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 6 – Sensing & Detection                           ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "Sensing & Detection", "Dynamic sensing to detect VT/VF while avoiding oversensing");

  const cards = [
    { title: "3 Sensing Vectors", body: "Distal tip → can\nProximal ring → can\nDistal tip → proximal ring\n\nBest vector chosen at implant", x: 0.3, y: 1.45, c: "E3F2FD" },
    { title: "Pre-implant Screening", body: "Surface ECG screening using 3 sensing vectors\n7–10% of candidates fail screening\nAssesses R:T wave ratio to predict oversensing", x: 3.55, y: 1.45, c: "E8F5E9" },
    { title: "Dynamic Sensing", body: "Sensitivity adjusts after each sensed event\nPrevents T-wave oversensing\nTailored to variable VF signal amplitude", x: 6.8, y: 1.45, c: "FFF8E1" },
    { title: "SMART Pass™ / Morphology Filter", body: "Manufacturer algorithms compare EGM morphology to template\nReduces inappropriate therapy for SVT and AF\nDifferentiates R waves from T waves by dV/dt", x: 0.3, y: 3.5, c: "FCE4EC" },
    { title: "Detection Zones", body: "Conditional zone: morphology discrimination applied\nShock zone: immediate therapy — no delay\nDuration criteria: number of fast intervals required", x: 3.55, y: 3.5, c: "EDE7F6" },
    { title: "Post-shock Pacing", body: "30 seconds of transcutaneous backup pacing at 50 bpm post-shock\nNOT a substitute for permanent bradycardia pacing", x: 6.8, y: 3.5, c: "E0F2F1" },
  ];

  cards.forEach(card => {
    s.addShape(pres.shapes.ROUNDED_RECTANGLE, { x: card.x, y: card.y, w: 3.0, h: 1.85, fill: { color: card.c }, line: { color: TEAL, pt: 1 }, rectRadius: 0.1, shadow: { type: "outer", color: "000000", blur: 5, offset: 2, angle: 135, opacity: 0.12 } });
    s.addText(card.title, { x: card.x + 0.1, y: card.y + 0.08, w: 2.8, h: 0.38, fontSize: 12, bold: true, color: NAVY, fontFace: "Calibri", margin: 0 });
    s.addText(card.body, { x: card.x + 0.1, y: card.y + 0.45, w: 2.8, h: 1.35, fontSize: 10.5, color: "333333", fontFace: "Calibri", valign: "top" });
  });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 7 – Advantages                                    ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: NAVY }, line: { color: NAVY } });
  // teal accent
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 0.18, h: 5.625, fill: { color: TEAL }, line: { color: TEAL } });

  s.addText("Advantages of S-ICD", { x: 0.4, y: 0.25, w: 9, h: 0.7, fontSize: 26, bold: true, color: WHITE, fontFace: "Calibri", margin: 0 });
  s.addShape(pres.shapes.RECTANGLE, { x: 0.4, y: 0.95, w: 9, h: 0.05, fill: { color: TEAL }, line: { color: TEAL } });

  const advs = [
    { icon: "★", title: "No transvenous leads", desc: "Eliminates vascular access complications (pneumothorax, cardiac perforation, venous thrombosis)" },
    { icon: "★", title: "Lower systemic infection risk", desc: "No intravascular hardware — pocket infection rate ~1.1%; systemic infections not reported in major series" },
    { icon: "★", title: "No lead extraction hazard", desc: "Lead removal is straightforward subcutaneous procedure — avoids high-risk transvenous extraction" },
    { icon: "★", title: "Preserved venous access", desc: "All central veins remain intact for future IV access, hemodialysis, or future CRT if needed" },
    { icon: "★", title: "Ideal for young/channelopathy patients", desc: "Avoids decades of transvenous lead failure risk in Brugada, LQTS, HCM, ARVC patients" },
    { icon: "★", title: "Reduced procedural risk", desc: "Implant does not require fluoroscopy; no intravascular manipulation" },
  ];

  advs.forEach((a, i) => {
    const col = i < 3 ? 0 : 1;
    const row = i % 3;
    const x = 0.4 + col * 5.0;
    const y = 1.15 + row * 1.42;
    s.addShape(pres.shapes.RECTANGLE, { x, y, w: 4.7, h: 1.28, fill: { color: "0D2B5E" }, line: { color: TEAL, pt: 1 } });
    s.addText(a.icon + "  " + a.title, { x: x + 0.15, y: y + 0.08, w: 4.4, h: 0.38, fontSize: 13, bold: true, color: TEAL, fontFace: "Calibri", margin: 0 });
    s.addText(a.desc, { x: x + 0.15, y: y + 0.44, w: 4.4, h: 0.75, fontSize: 11, color: GRAY, fontFace: "Calibri", valign: "top" });
  });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 8 – Limitations & Complications                   ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "Limitations & Complications", "Compared with transvenous ICD systems");

  // Limitations box left
  s.addShape(pres.shapes.RECTANGLE, { x: 0.3, y: 1.4, w: 4.4, h: 3.9, fill: { color: "FFF9C4" }, line: { color: "F9A825", pt: 1.5 } });
  s.addText("⚠  LIMITATIONS", { x: 0.4, y: 1.45, w: 4.1, h: 0.42, fontSize: 13, bold: true, color: "E65100", fontFace: "Calibri", margin: 0 });
  s.addText([
    bullet("No anti-tachycardia pacing (ATP)"),
    bullet("No anti-bradycardia pacing (permanent)"),
    bullet("No cardiac resynchronization therapy (CRT)"),
    bullet("Higher rate of inappropriate shocks: 5–10% vs <2%/year for transvenous ICD"),
    bullet("7–10% of candidates fail pre-implant ECG screening"),
    bullet("Larger generator size — more conspicuous pocket"),
    bullet("Shorter battery longevity than transvenous ICD"),
    bullet("Cannot deliver ATP for pace-terminable VT"),
  ], { x: 0.4, y: 1.9, w: 4.2, h: 3.25, valign: "top" });

  // Complications box right
  s.addShape(pres.shapes.RECTANGLE, { x: 5.2, y: 1.4, w: 4.4, h: 3.9, fill: { color: "FFEBEE" }, line: { color: "C62828", pt: 1.5 } });
  s.addText("✘  COMPLICATIONS", { x: 5.3, y: 1.45, w: 4.1, h: 0.42, fontSize: 13, bold: true, color: "C62828", fontFace: "Calibri", margin: 0 });
  s.addText([
    bullet("Inappropriate shocks — most common complication"),
    bullet("  • T-wave oversensing"),
    bullet("  • Myopotential oversensing"),
    bullet("  • Double R-wave counting"),
    bullet("Pocket infection: ~1.1% (lower than transvenous)"),
    bullet("Lead migration / dislodgement"),
    bullet("Pocket hematoma"),
    bullet("Wound dehiscence"),
    bullet("No vascular access, pneumothorax, or lead endocarditis"),
  ], { x: 5.3, y: 1.9, w: 4.2, h: 3.25, valign: "top" });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 9 – Inappropriate Shocks                          ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "Inappropriate Shocks", "The most important complication of S-ICD");

  s.addShape(pres.shapes.RECTANGLE, { x: 0.3, y: 1.35, w: 9.4, h: 0.68, fill: { color: "FFCDD2" }, line: { color: "C62828", pt: 1 } });
  s.addText("Rate: 5–10% in year 1 (vs. <2% with modern transvenous ICD). New sensing algorithms have reduced but not eliminated this risk.", {
    x: 0.5, y: 1.43, w: 9.0, h: 0.54, fontSize: 13, bold: true, color: "B71C1C", fontFace: "Calibri", valign: "middle"
  });

  const causes = [
    { title: "T-wave oversensing", body: "Most common. S-ICD sees T-wave as a second R-wave → double counts → detects VF. Minimised by screening and sensing vector selection." },
    { title: "Myopotential oversensing", body: "Signals from chest wall muscles (pectoralis, diaphragm) sensed as cardiac activity. More common with unipolar or suboptimal vectors." },
    { title: "Supraventricular tachycardia (SVT)", body: "Rapid SVT/AF detected in shock zone before morphology discrimination can suppress therapy. Rate-based detection at limits." },
    { title: "R-wave double counting", body: "Wide QRS (LBBB, ventricular pacing) or fragmented QRS counted twice per beat — appears as VF rate. Detected by pre-implant screening." },
  ];

  causes.forEach((c, i) => {
    const x = 0.3 + (i % 2) * 4.85;
    const y = 2.15 + Math.floor(i / 2) * 1.7;
    s.addShape(pres.shapes.ROUNDED_RECTANGLE, { x, y, w: 4.5, h: 1.55, fill: { color: WHITE }, line: { color: TEAL, pt: 1.5 }, rectRadius: 0.1 });
    s.addText(c.title, { x: x + 0.15, y: y + 0.1, w: 4.2, h: 0.38, fontSize: 13, bold: true, color: NAVY, fontFace: "Calibri", margin: 0 });
    s.addText(c.body, { x: x + 0.15, y: y + 0.46, w: 4.2, h: 1.0, fontSize: 11, color: "444444", fontFace: "Calibri", valign: "top" });
  });

  s.addShape(pres.shapes.RECTANGLE, { x: 0.3, y: 5.2, w: 9.4, h: 0.3, fill: { color: "E3F2FD" }, line: { color: TEAL, pt: 1 } });
  s.addText("Prevention: Careful sensing vector selection at implant | SMART Pass algorithm | Conditional zone morphology discrimination", {
    x: 0.4, y: 5.22, w: 9.1, h: 0.26, fontSize: 10, color: NAVY, fontFace: "Calibri", italic: true
  });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 10 – Pre-implant Screening                        ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "Pre-implant ECG Screening", "Mandatory before S-ICD implantation");

  s.addText([
    bulletBold("Purpose"),
    bullet("Identify patients at high risk for inappropriate shocks from T-wave oversensing or R-wave double counting", 1),
    bullet("7–10% of candidates fail and should not receive an S-ICD", 1),
    { text: "", options: { breakLine: true } },
    bulletBold("Method — SICD Screening Tool"),
    bullet("Electrode positions simulate S-ICD sensing vectors using surface ECG electrodes", 1),
    bullet("Three sensing vectors tested in supine and standing positions", 1),
    bullet("R:T amplitude ratio assessed — R wave must be clearly larger than T wave", 1),
    bullet("At least one vector must pass in both positions", 1),
    { text: "", options: { breakLine: true } },
    bulletBold("Causes of Screening Failure"),
    bullet("Tall T-waves relative to R-waves (e.g., Brugada type I pattern, LVH, electrolyte disturbance)", 1),
    bullet("Low-amplitude R waves", 1),
    bullet("Wide QRS with morphology changes", 1),
    { text: "", options: { breakLine: true } },
    bulletBold("Clinical Note"),
    bullet("Screening should be repeated in different body positions and with exercise if borderline", 1),
    bullet("Patients with channelopathies (Brugada) may have dynamic changes — screen at rest and provoked", 1),
  ], { x: 0.5, y: 1.4, w: 5.3, h: 4.0, valign: "top" });

  // Right: summary info box
  s.addShape(pres.shapes.ROUNDED_RECTANGLE, { x: 6.1, y: 1.4, w: 3.55, h: 3.9, fill: { color: NAVY }, line: { color: TEAL, pt: 2 }, rectRadius: 0.12 });
  s.addText("Screening Pass Criteria", { x: 6.2, y: 1.55, w: 3.3, h: 0.45, fontSize: 14, bold: true, color: TEAL, fontFace: "Calibri", margin: 0, align: "center" });
  s.addShape(pres.shapes.RECTANGLE, { x: 6.3, y: 2.0, w: 3.15, h: 0.04, fill: { color: TEAL }, line: { color: TEAL } });

  const criteria = [
    "≥1 of 3 sensing vectors must pass",
    "Must pass in BOTH supine & standing",
    "R wave clearly dominant over T wave",
    "No R-wave double counting",
    "Failure rate: 7–10%",
  ];
  criteria.forEach((c, i) => {
    s.addText("→  " + c, { x: 6.2, y: 2.18 + i * 0.58, w: 3.3, h: 0.5, fontSize: 12, color: WHITE, fontFace: "Calibri", valign: "middle" });
  });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 11 – Key Clinical Trials                          ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: "F4F7FA" }, line: { color: "F4F7FA" } });
  addHeader(s, "Key Clinical Trials & Evidence", "Supporting evidence base for S-ICD");

  const trials = [
    { name: "PRAETORIAN Trial (2020)", result: "Non-inferior to transvenous ICD for complications + inappropriate shocks over 4 years. S-ICD: 15.1% events vs TV-ICD: 15.7%", color: "E3F2FD" },
    { name: "UNTOUCHED Trial (2020)", result: "Inappropriate shock rate reduced to 4.0% at 18 months with dual-zone programming + SMART Pass in low-EF patients", color: "E8F5E9" },
    { name: "EFFORTLESS Registry", result: "Prospective S-ICD registry. Confirmed safety and efficacy. Inappropriate shock rate declined over time with improved algorithms", color: "FFF9C4" },
    { name: "Pooled S-ICD IDE Trial", result: "First pivotal trial. Conversion success 98.2% for induced VF. Appropriate therapy 100% at 11 months follow-up", color: "F3E5F5" },
  ];

  trials.forEach((t, i) => {
    const y = 1.4 + i * 1.04;
    s.addShape(pres.shapes.ROUNDED_RECTANGLE, { x: 0.3, y, w: 9.4, h: 0.95, fill: { color: t.color }, line: { color: TEAL, pt: 1 }, rectRadius: 0.08 });
    s.addText(t.name, { x: 0.5, y: y + 0.08, w: 2.8, h: 0.38, fontSize: 13, bold: true, color: NAVY, fontFace: "Calibri", margin: 0 });
    s.addText(t.result, { x: 3.3, y: y + 0.08, w: 6.2, h: 0.78, fontSize: 12, color: "333333", fontFace: "Calibri", valign: "middle" });
  });

  s.addText("Source: Braunwald's Heart Disease 2024 | PRAETORIAN NEJM 2020 | UNTOUCHED JACC 2020", {
    x: 0.3, y: 5.3, w: 9.4, h: 0.22, fontSize: 9, color: GRAY, italic: true, fontFace: "Calibri"
  });
}

// ╔══════════════════════════════════════════════════════════╗
// ║  SLIDE 12 – Summary / Key Takeaways                      ║
// ╚══════════════════════════════════════════════════════════╝
{
  const s = pres.addSlide();
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 5.625, fill: { color: NAVY }, line: { color: NAVY } });
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 0.18, h: 5.625, fill: { color: TEAL }, line: { color: TEAL } });

  s.addText("Key Takeaways", { x: 0.4, y: 0.2, w: 9, h: 0.65, fontSize: 28, bold: true, color: WHITE, fontFace: "Calibri", margin: 0 });
  s.addShape(pres.shapes.RECTANGLE, { x: 0.4, y: 0.85, w: 9, h: 0.06, fill: { color: TEAL }, line: { color: TEAL } });

  const pts = [
    "S-ICD uses no intravascular or intracardiac leads — generator in left lateral chest, lead along parasternal border.",
    "Best for patients who need shock protection only — no pacing, ATP, or CRT required.",
    "Eliminates transvenous lead complications: vascular injury, lead extraction risk, and systemic infection.",
    "Pre-implant ECG screening is mandatory — 7–10% of candidates fail due to T-wave oversensing risk.",
    "Inappropriate shocks (5–10%/yr) are the dominant complication; new sensing algorithms (SMART Pass) are reducing this.",
    "PRAETORIAN trial confirmed non-inferiority to transvenous ICD for overall adverse events.",
    "Future development: wireless pairing with leadless pacemakers will extend functionality to pacing-dependent patients.",
  ];

  pts.forEach((p, i) => {
    const y = 1.05 + i * 0.63;
    s.addShape(pres.shapes.RECTANGLE, { x: 0.4, y, w: 0.45, h: 0.45, fill: { color: TEAL }, line: { color: TEAL } });
    s.addText(String(i + 1), { x: 0.4, y: y + 0.02, w: 0.45, h: 0.41, fontSize: 14, bold: true, color: WHITE, align: "center", fontFace: "Calibri", margin: 0 });
    s.addText(p, { x: 1.05, y: y + 0.03, w: 8.5, h: 0.5, fontSize: 12, color: WHITE, fontFace: "Calibri", valign: "middle" });
  });
}

// ─── Write file ──────────────────────────────────────────
pres.writeFile({ fileName: "/home/daytona/workspace/sicd-ppt/Subcutaneous_ICD.pptx" })
  .then(() => console.log("PPTX written successfully"))
  .catch(e => { console.error("Error:", e); process.exit(1); });

You've run out of free credits. Sign up for a free account to continue using Orris.

This is a shared conversation. Sign in to Orris to start your own chat.