Mortality Causes in Post-Cardiac Surgery Patients with Perimembranous VSD

Immediate Postoperative Mortality Mechanisms

The American College of Cardiology states that PHC represents the most critical immediate postoperative complication, occurring in 2-7% of patients undergoing congenital cardiac surgery, with associated mortality of 20% in recent series 1
PHC accounts for 8% mortality within the first month after repair of certain defects, and PHC episodes are strongly associated with high risk for late death 1
The American Heart Association notes that when RV pressure rises above aortic pressure in systole and diastole, coronary perfusion becomes impaired, causing cardiac ischemia and dysfunction 1
The presence of severely elevated pulmonary vascular resistance incurs high perioperative risk, particularly when pulmonary vascular resistance exceeds 2/3 systemic levels, as stated by the American College of Cardiology 2, 3

The American College of Cardiology recommends that closure of nonrestrictive VSD in adults with Eisenmenger syndrome who do not demonstrate left-to-right shunting should not be performed due to high mortality risk 2, 3
Larger defects may be repaired only in the absence of severe pulmonary hypertension and severely elevated pulmonary vascular resistance, the presence of which incurs high perioperative risk, as noted by the American College of Cardiology 2, 5
Surgery is contraindicated when PA systolic pressure exceeds 2/3 systemic and pulmonary vascular resistance exceeds 2/3 systemic, according to the American College of Cardiology 4

Infective endocarditis occurs in up to 2 per 1000 patient-years in patients with small residual VSDs, with a 6-fold increased risk compared to the general population, as stated by the American Heart Association 6
The risk of IE increases in patients with unrepaired VSD, typically involving the tricuspid and pulmonic valves, according to the American College of Cardiology 2, 3, 5
Residual shunts at or adjacent to prosthetic patches that inhibit endothelialization remain high-risk for complications, including IE, as noted by the American College of Cardiology 6

Patients with genetic syndromes, chromosomal abnormalities, or extracardiac anomalies have a high incidence of lung hypoplasia and difficult postoperative courses complicated by simplified pulmonary vascular bed, as stated by the American Heart Association 1
Ventricular arrhythmias can contribute to sudden cardiac death in the late postoperative period, according to the American Heart Association 7

The American College of Cardiology advises against proceeding with emergency surgery in cardiogenic shock within 72 hours if mechanical circulatory support can stabilize the patient, as mortality approaches 100% with immediate surgery versus improved outcomes with delayed repair 6
The American Heart Association recommends avoiding closure in patients with Eisenmenger physiology and non-reactive pulmonary vascular disease, as this carries prohibitively high mortality 2, 3
Maintaining vigilance for respiratory management issues, including pulmonary edema, atelectasis, ventilation-perfusion mismatch, and bronchoconstriction, is crucial for preventing PHC, as stated by the American Heart Association 1