Mortality and morbidity of patients on the waiting list for coronary artery bypass graft surgery.

OBJECTIVES: The public health care system in Brazil has extensive waiting lists of patients requiring complex operations such as coronary artery bypass grafting (CABG). The purpose of this study was to identify the mortality and morbidity rates of the patients awaiting CABG and identify predictors of adverse events and their association with perioperative outcomes. METHODS: We conducted a retrospective analysis of outpatient medical records of patients referred for this elective procedure in Rio de Janeiro, Brazil. Excluded from the study were records of patients with any of the following: an indication for urgent surgery, unstable angina or concomitant surgical valvular disease or subsequent transfer to clinical or percutaneous therapy. RESULTS: A total of 274 patients were identified and met the inclusion criteria, with a median waiting time for an operation of 142.7 days. While waiting for CABG surgery, 31 (11.3%) patients died of any cause and 42 (15.3%) patients had a serious cardiac event (death, myocardial infarction or unstable angina). Of the 22 (8%) incidents of acute myocardial infarction, 8 (2.9%) were non-fatal and 14 (5.1%) were fatal. There was a greater risk of death awaiting CABG surgery in patients with a left ventricular ejection fraction below 45% (hazard ratio = 2.33, 95% confidence interval 1.02-5.32; P = 0.039). The operative mortality rate was 5.8%. Although there was no evidence of worse perioperative outcomes in patients with prolonged waiting times for an operation, there was an association between waiting more than 16 weeks for an operation and death while on the list. CONCLUSIONS: Extensive waiting periods for CABG contribute to higher mortality and morbidity rates, especially in patients with left ventricular dysfunction.

Left atrial myxoma associated with obstructive coronary artery disease.

We describe a case of a 67 year-old patient with obstructive coronary artery disease that, in the preoperative survey for inguinal herniorraphy surgery, discovered, by a two-dimensional echocardiogram, a tumor in left atrium, mobile, non-obstructive. The patient underwent a cineangiocoronariography showing severe stenosis in the left anterior descending artery, moderate stenosis in the left circumflex artery, near the origin of the first marginal branch, and a non-obstructive plaque in the right coronary artery. There was also moderate left ventricular dysfunction. After that, the patient has gone coronary artery bypass surgery and resection of the left atrial tumor. The histological exam revealed that the tumor was, in fact, a myxoma.

Functional assessment of coronary grafts on dobutamine pharmacological stress echocardiogram.

OBJECTIVE: To verify the sensitivity, specificity and diagnostic accuracy of dobutamine stress echocardiogram (DSE) when assessing the functional status of coronary grafts: sufficient (SUF) or insufficient (INS). METHODS: We carried out a prospective, observational study which included 25 patients submitted to coronary artery bypass grafting (CABG). The DSE and the coronary angiography were performed before the CABG and three months after the CABG. The left ventricle was divided into three territories per patient according to the three major coronary arterie: the anterior descending (AD), the circumflex (CX) and the right coronary (RC). Of the 75 possible territories, 54 were revascularized: 25 were specific to the AD artery and 29 of the CX/RC arteries. INS means luminal obstruction or occlusion greater than or equal to 50%. RESULTS: In 14 (26%) of the 54 revascularized territories the grafts were INS. The DSE detected ischemia in 16 (28%) territories; 10 of which had INS grafts. The DSE detected ischemia in 6 (15%) of the 40 territories whose grafts were SUF. Therefore, the DSE had a sensitivity of 71.4%, specificity of 85% and diagnostic accuracy of 81.4%. CONCLUSION: The DSE is a diagnostic method with high specificity and diagnostic accuracy, and good sensitivity for the functional assessment of coronary grafts.

Can patients with left main coronary artery disease wait for myocardial revascularization surgery?

OBJECTIVE: To assess the occurrence of cardiac events in patients diagnosed with left main coronary artery disease on diagnostic cardiac catheterization and waiting for myocardial revascularization surgery. METHODS: All patients diagnosed with left main coronary artery disease (stenosis > or = 50%) consecutively identified on diagnostic cardiac catheterization during an 8-month period were selected for the study. The group comprised 56 patients (40 males and 16 females) with a mean age of 61 10 years. The cardiac events included death, nonfatal acute myocardial infarction, acute left ventricular failure, unstable angina, and emergency surgery. RESULTS: While waiting for surgery, patients experienced the following cardiac events: 7 acute myocardial infarctions and 1 death. All events occurred within the first 60 days after the diagnostic cardiac catheterization. More patients, whose indication for diagnostic cardiac catheterization was unstable angina, experienced events as compared with those with other indications [p=0.03, relative risk (RR) = 5.25, 95% confidence interval = 1.47 - 18.7]. In the multivariate analysis of logistic regression, unstable angina was also the only factor that independently contributed to a greater number of events (p = 0.02, OR = 8.43, 95% CI =1.37 - 51.7). CONCLUSION: Unstable angina in patients with left main coronary artery disease acts as a high risk factor for cardiac events, emergency surgery being recommended in these cases.

Improvement in left ventricular dysfunction after surgical correction of mitral regurgitation.

OBJECTIVE: To evaluate whether left ventricular end-systolic (ESD) diameters < or = 51mm in patients (pt) with severe chronic mitral regurgitation (MR) are predictors of a poor prognosis after mitral valve surgery (MVS). METHODS: Eleven pt (aged 36 +/- 13 years) were studied in the preoperative period (pre), median of 36 days; in the early postoperative period (post1), median of 9 days; and in the late postoperative period (post2), mean of 38.5 +/- 37.6 months. Clinical and echocardiographic data were gathered from each pt with MR and systolic diameter > or = 51 mm (mean = 57 +/- 4mm) to evaluate the result of MVS. Ten patients were in NYHA Class III/IV. RESULTS: All but 2 pt improved in functional class. Two pt died from heart failure and infectious endocarditis 14 and 11 months, respectively, after valve replacement. According to ejection fraction (EF) in post2, we identified 2 groups: group 1 (n=6), whose EF decreased in post1, but increased in post2 (p=0.01) and group 2 (n=5), whose EF decreased progressively from post1 to post2 (p=0.10). All pt with symptoms lasting < or = 48 months had improvement in EF in post2 (p=0.01). CONCLUSION: ESD > or = 51 mm are not always associated with a poor prognosis after MVS in patients with MR. Symptoms lasting up to 48 months are associated with improvement in left ventricular function.