What to do in a patient with Dilated Cardiomyopathy (DCMP), with a severely impaired left ventricular function (Ejection Fraction (EF) of 15%) and experiencing recurrent unsustained Ventricular Tachycardia (VT) with spontaneous conversion to sinus tachycardia, who has been given misoprostol (prostaglandin E1 analogue) for labor induction?

Management of Dilated Cardiomyopathy with Severe LV Dysfunction, Recurrent Unsustained VT, and Misoprostol-Induced Labor

This patient requires immediate multidisciplinary critical care with continuous cardiac monitoring, aggressive hemodynamic stabilization, consideration for ICD placement after delivery, and urgent obstetric consultation to expedite delivery given the life-threatening cardiac status. 1

Immediate Stabilization and Monitoring

Hemodynamic Assessment:

• Assess immediately for signs of hypoperfusion (altered mental status, poor capillary refill, decreased urine output) and congestion (elevated jugular venous pressure, pulmonary edema) 1
• Measure vital signs continuously, particularly blood pressure, as misoprostol can cause hypotension that compounds the already severely compromised hemodynamics (EF 15%) 1, 2
• Perform invasive hemodynamic monitoring if respiratory distress or impaired perfusion is present and filling pressures cannot be determined clinically 1

Cardiac Monitoring:

• Continuous telemetry monitoring is mandatory given recurrent unsustained VT in the setting of severe LV dysfunction (EF 15%) 3
• Monitor for progression to sustained VT or ventricular fibrillation, which would require immediate cardioversion 3

Critical Medication Management

Continue Guideline-Directed Medical Therapy:

• Continue ACE inhibitors/ARBs and beta-blockers unless frank hemodynamic instability exists (hypotension with hypoperfusion), as discontinuation worsens outcomes even during acute decompensation 1
• Avoid intravenous nondihydropyridine calcium channel antagonists (verapamil, diltiazem) as they may exacerbate hemodynamic compromise 1

Manage Congestion:

• Administer intravenous loop diuretics aggressively if clinical evidence of congestion exists (elevated JVP, pulmonary edema) 1
• Consider intravenous nitroglycerin or nitroprusside when added to diuretics if severely symptomatic fluid overload exists without systemic hypotension 1

Inotropic Support if Needed:

• Administer intravenous inotropic or vasopressor drugs if clinical hypotension with hypoperfusion exists alongside elevated cardiac filling pressures 1

Management of Unsustained Ventricular Tachycardia

The recurrent unsustained VT in this patient with DCMP and EF 15% places her at extremely high risk for sudden cardiac death and warrants ICD consideration post-delivery.

Acute VT Management:

• Beta-blockers are first-line for rate control and arrhythmia suppression, provided hemodynamic stability allows 3
• Amiodarone, often in combination with beta-blockers, can be useful for patients with LV dysfunction and symptomatic VT unresponsive to beta-blockers alone 3
• If sustained VT develops with hemodynamic compromise, immediate synchronized cardioversion is indicated 3

ICD Indication Post-Delivery:

• ICD implantation is indicated (Class I recommendation) for this patient with nonischemic dilated cardiomyopathy, LVEF ≤35% (she has 15%), and NYHA functional class II-III symptoms, provided meaningful survival >1 year is expected 3
• The presence of unsustained VT further supports ICD candidacy, though it is not required for the indication given the severely reduced EF 3
• ICD therapy reduces all-cause mortality by 23% in patients with heart failure and EF ≤35% 3

Obstetric Management Considerations

Misoprostol-Related Concerns:

• Misoprostol causes uterine hyperstimulation in 11.7 times more patients compared to placebo (95% CI 2.78-49) 4
• Uterine hyperstimulation with fetal heart rate changes occurs 1.45 times more frequently with misoprostol versus other prostaglandins (95% CI 1.04-2.04) 2, 4
• The cardiovascular stress from labor combined with misoprostol-induced hypotension and tachycardia poses extreme risk in this patient with EF 15% 2, 5

Delivery Planning:

• Urgent obstetric consultation to determine optimal timing and mode of delivery 3
• Epidural anesthesia can be considered if hemodynamics are stable, as it reduces cardiovascular stress during delivery 3
• Intensive cardiac monitoring is needed during labor and delivery, with immediate access to cardioversion/defibrillation equipment 3
• Consider early cesarean delivery if vaginal delivery poses excessive hemodynamic risk 3

Critical Pitfalls to Avoid

• Do not reflexively discontinue GDMT (ACE inhibitors/ARBs, beta-blockers) during acute decompensation unless frank hemodynamic instability exists 1
• Do not delay ICD evaluation post-delivery; this patient meets clear Class I criteria for primary prevention ICD with EF 15% and nonischemic cardiomyopathy 3
• Do not use calcium channel blockers (verapamil, diltiazem) for rate control as they worsen heart failure 1
• Monitor closely for progression from unsustained to sustained VT, which would require immediate intervention 3
• Recognize that even after successful rhythm control and EF improvement, sudden death risk persists, requiring long-term ICD protection 6

Post-Delivery Management

GDMT Optimization:

• Ensure all four mortality-reducing medication classes are initiated/optimized: renin-angiotensin system inhibitors, evidence-based beta-blockers, mineralocorticoid receptor antagonists, and SGLT2 inhibitors (each reduces mortality by ≥20%) 1
• Start beta-blockers at low doses only after volume optimization and discontinuation of intravenous diuretics, vasodilators, and inotropes 1

ICD Implantation:

• Proceed with ICD implantation once hemodynamically stable, ideally before hospital discharge or within weeks post-delivery 3
• ICD should be programmed to minimize unnecessary right ventricular pacing, which can worsen heart failure 3

Close Follow-Up:

• Ensure outpatient cardiology follow-up within 7-14 days to continue GDMT optimization 1
• Daily weights and careful fluid intake/output monitoring 1
• Monitor for supine and upright hypotension with all medication changes 1