Postinfarction ventricular septal defect

Using extracorporeal membrane oxygenation support preoperatively and postoperatively as a successful bridge to recovery in a patient with a large infarct-induced ventricular septal defect

Rupture of the ventricular septum during acute myocardial infarction usually occurs within the first week. The event is usually followed by low cardiac output, heart failure, and multiorgan failure. Despite the many advances in the nonoperative treatment of heart failure and cardiogenic shock, including the intra-aortic balloon pump and a multitude of new inotropic agents and vasodilators, these do not supplant the need for operative intervention in these critically ill patients. This article describes the successful use of extracorporeal membrane oxygenation support as a bridge to recovery postoperatively in a patient with a large infarct-produced ventricular septal defect.

The formation of an anti-restenotic/anti-thrombotic surface by immobilization of nitric oxide synthase on a metallic carrier

Coronary stenosis due to atherosclerosis, the primary cause of coronary artery disease, is generally treated by balloon dilatation and stent implantation, which can result in damage to the endothelial lining of blood vessels. This leads to the restenosis of the lumen as a consequence of migration and proliferation of smooth muscle cells (SMCs). Nitric oxide (NO), which is produced and secreted by vascular endothelial cells (ECs), is a central anti-inflammatory and anti-atherogenic player in the vasculature. The goal of the present study was to develop an enzymatically active surface capable of converting the prodrug l-arginine, to the active drug, NO, thus providing a targeted drug delivery interface. NO synthase (NOS) was chemically immobilized on the surface of a stainless steel carrier with preservation of its activity. The ability of this functionalized NO-producing surface to prevent or delay processes involved in restenosis and thrombus formation was tested. This surface was found to significantly promote EC adhesion and proliferation while inhibiting that of SMCs. Furthermore, platelet adherence to this surface was markedly inhibited. Beyond the application considered here, this approach can be implemented for the local conversion of any systemically administered prodrug to the active drug, using catalysts attached to the surface of the implant.

Surgery for post-infarction ventricular septal defect (VSD): double patch and glue technique for early repair

Repair of post-infarction ventricular septal defect (VSD) remains a challenging procedure with a high risk of VSD recurrence. In order to reduce this risk, a double patch and glue technique was introduced in the department in 1986. This surgical technique is hereunder presented. Since 1971, ninety-three patients have been operated on early (≪15 days) after the occurrence of a post-infarction VSD. This retrospective study allows to compare the results of this double patch and glue technique to those obtained with the conventional one, in terms of hospital death and VSD recurrence. The double patch and glue technique avoids recurrence of VSD and plays a part in reducing hospital mortality.

Surgical Repair of Mechanical Complications of Myocardial Infarction

Mechanical complications of acute myocardial infarction are estimated to account for 25,000 fatalities yearly in the United States. The diagnosis necessitates a high degree of clinical suspicion. Once recognized, prompt surgical intervention is necessary because if left untreated the condition frequently causes a fatal outcome. The main determinants of survival are the preoperative hemodynamic status of the patient, the presence of multisystem failure at presentation, and concomitant revascularization during repair of the defect. Because ischemic heart disease remains the leading cause of death in such patients following repair, coronary artery bypass should be considered and, whenever possible, performed in conjunction with repair of the postinfarct mechanical complication.

Ventricular Septal Rupture After Early Successful Thrombolytic Therapy in Acute Myocardial Infarction: A Case Report

Ventricular septal defect (VSD) is a severe complication of acute myocardial infarction and has a high mortality rate. This complication appears to have declined in the reperfusion era. It has mostly been reported in elderly or female patients who suffer from anterior wall infarction, patients with multivessel coronary artery disease (CAD) or occluded infarct-related artery (IRA) without collateral circulation, or patients who have had delayed reperfusion therapy. Here, we report the case of a 60-year-old male patient who presented with persistent chest pain and Killip I ST-segment-elevation myocardial infarction. Thrombolytic therapy was started 3 hours after the onset of chest pain. Based on the subsidence of chest pain, resolution of the elevated ST segment, and early peak of cardiac enzymes, reperfusion was thought to be successful. However, on the third day of admission, the patient complained of dyspnea after defecation and was found to have new-onset grade 3 pansystolic murmur over the left sternal border. Cardiac echography showed an apical VSD. A Swan-Ganz catheter was inserted into the right side of the heart; analysis of blood oxygen saturation revealed a 6% step-up of oxygen in the right ventricle. Coronary angiography showed only one-vessel CAD and TIMI 3 flow in the IRA. The patient received intensive medical management and underwent VSD repair and internal mammary artery bypass grafting to the left anterior descending artery. His recovery was uneventful. This case illustrates that VSD can be found in patients receiving early successful reperfusion therapy, with one-vessel CAD, and TIMI 3 flow in the IRA.

Review of ventricular rupture: key concepts and diagnostic tools for success

Although a rare complication of acute myocardial infarction (AMI), ventricular rupture is a serious event associated with significant mortality and morbidity. Patients normally present with hemodynamic instability, often in cardiogenic shock. Despite improvements in surgical techniques and diagnostic tools, post-myocardial infarction ventricular rupture remains a difficult therapeutic challenge. There are three categories of ventricular rupture: free wall rupture (FWR), ventricular septal rupture (VSR), and papillary muscle rupture (PWR). The incidence of FWR occurs following up to 10% of myocardial infarctions. VSR and PWR have a lower incidence of 1-2% and 0.5-5%, respectively. Patients often present with single-vessel coronary artery disease and usually do not have a positive history for a previous myocardial infarction. The incidence of post infarction angina in these patients is significantly greater than in patients without ventricular rupture. Delay in treatment and continued physical activity post infarction increases the risk of ventricular rupture. Diagnostic tools such as two-dimensional echocardiography and cardiac catheterization confirm the diagnosis of ventricular rupture in only 45-88% of cases. Knowledge of the disease progression is necessary to insure accurate and timely diagnosis. Due to the rapid deterioration of these patients, there is a 50-80% mortality rate within the first week if untreated. With surgical correction, patients can extend their 5-year survival rates to 65%. A good example of the complex course of ventricular rupture is the case of a 71-year-old patient at our institution. The patient presented in cardiogenic shock following an AMI. Preoperative diagnosis was unsuccessful in determining the extent of the ventricular rupture. The correct diagnosis was determined in the operating room, and both a mitral valve replacement and closure of a ventricular septal defect were completed. The patient was successfully treated with this difficult pathology.

Post infarction ventricular septal defect - can we do better?

OBJECTIVE

To identify predictors of early and late outcome among 117 consecutive patients who underwent postinfarction ventricular septal defect (VSD) repair over a period of 12 years.

METHODS

A retrospective analysis of clinical data was performed. Mean age was 65.5+/-7.8. There were 43 females. Full data were obtained in 110 patients. Of these, 76 patients presented with anterior and 34 with posterior VSD. Thirty-three patients were operated in cardiogenic shock. Mean time between myocardial infarction (MI) and VSD development was 5.6+/-7.8 days (median 4) and from VSD to surgery 9. 0+/-28.1 (median 2). Sixty-six patients had intraaortic balloon pump (IABP) inserted, and 15 were ventilated preoperatively. Logistic regression and Cox regression were used for multivariate analysis.

RESULTS

Thirty days mortality was 37%. Among 110 patients, in whom complete analysis was possible, 38 died within 30 days (35%). Mortality in the posterior VSD group was 35% and in the anterior VSD group 34% (NS). In 44 patients (40%) a residual shunt was found on postoperative echocardiography. This required reoperation in 13 patients (four deaths). Cardiogenic shock prior to surgery adversely influenced early survival - odds ratio (OR) 5.7 (confidence interval (CI) 2.1-16.0) (P=0.0008). Deterioration of haemodynamic status in between admission and surgery was stronger predictor of mortality than shock on admission - OR 6.0 (CI 1.6-22.6) (P=0.008) vs. 3.1 (CI 1.0-9.3) (P=0.049). A longer time between MI and surgery favoured survival - OR 0.1 (CI 0.03-0.4) (P=0.002). The time period from the infarct to the septal rupture, but not from the rupture to surgery, appeared to be a significant predictor of survival - OR 0.2 (CI 0. 05-0.6) (P=0.008). Five years survival was 46+/-5%. Preoperative cardiogenic shock affected late survival - OR 2.7 (CI 1.5-4.9) (P=0. 001). Of 72 patients who survived 30 postoperative days, 12 (17%) were in New York Heart Association (NYHA) class III or IV and five (6.9%) in Canadian Cardiovascular Soceity (CCS) class III or IV at the last follow-up.

CONCLUSIONS

Preoperative cardiogenic shock and early postinfarction septal rupture carry a grave prognosis. Achieving haemodynamic stability prior to surgery may be beneficial but prolonged attempts to improve patients' cardiovascular state are hazardous.