Myocardial scintigraphy and clinical stratification as predictors of events in renal transplant candidates.

BACKGROUND: We tested the hypothesis that the universal application of myocardial scanning with single-photon emission computed tomography (SPECT) would result in better risk stratification in renal transplant candidates (RTC) compared with SPECT being restricted to patients who, in addition to renal disease, had other clinical risk factors. METHODS: RTCs (n=363) underwent SPECT and clinical risk stratification according to the American Society of Transplantation (AST) algorithm and were followed up until a major adverse cardiovascular event (MACE) or death. RESULTS: Of the 363 patients, 79 patients (22%) had an abnormal SPECT scan and 270 (74%) were classified as high risk. Both methods correctly identified patients with increased probability of MACE. However, clinical stratification performed better (sensitivity and negative predictive value 99% and 99% vs. 25% and 87%, respectively). High-risk patients with an abnormal SPECT scan had a modest increased risk of events (log-rank = 0.03; hazard ratio [HR] = 1.37; 95% confidence interval [95% CI], 1.02-1.82). Eighty-six patients underwent coronary angiography, and coronary artery disease (CAD) was found in 60%. High-risk patients with CAD had an increased incidence of events (log-rank = 0.008; HR=3.85; 95% CI, 1.46-13.22), but in those with an abnormal SPECT scan, the incidence of events was not influenced by CAD (log-rank = 0.23). Forty-six patients died. Clinical stratification, but not SPECT, correlated with the probability of death (log-rank = 0.02; HR=3.25; 95% CI, 1.31-10.82). CONCLUSION: SPECT should be restricted to high-risk patients. Moreover, in contrast to SPECT, the AST algorithm was also useful for predicting death by any cause in RTCs and for selecting patients for invasive coronary testing.

Influence of coronary artery disease assessment and treatment in the incidence of cardiac events in renal transplant recipients.

UNLABELLED: BACKGROUND: The best strategy for pre-transplant investigation and treatment of coronary artery disease (CAD) is controversial. METHODS: We evaluated 167 renal transplant recipients before transplantation to determine the incidence of cardiac events and death. We performed clinical evaluations and myocardial scans in all patients and coronary angiography in select patients. RESULTS: Asymptomatic patients with normal myocardial scans (n=57) had significantly fewer cardiac events (log-rank=0.0002) and deaths (log-rank=0.0005) than did patients with abnormal scans but no angiographic evidence of CAD (n=76) and individuals with CAD (n=34) documented angiographically. CAD increased the probability of events (HR=2.27, % CI 1.007-5.11; p=0.04). The incidence of cardiac events (log-rank=0.349) and deaths (log-rank=0.588) was similar among patients treated medically (n=23) or by intervention (n=11). CONCLUSION: Asymptomatic patients with normal myocardial scans had a better cardiac prognosis than did patients with or without CAD and positive for myocardial ischemia. Patients with altered scan and CAD had the poorer outcome. Guideline-oriented medical treatment is safe and yields results comparable to coronary intervention in renal transplant patients with CAD. The data do not support preemptive myocardial revascularization for renal transplant candidates.

Treatment of coronary artery disease in hemodialysis patients evaluated for transplant-a registry study.

BACKGROUND: We assessed the results of a noninvasive therapeutic strategy on the long-term occurrence of cardiac events and death in a registry of patients with chronic kidney disease (CKD) and coronary artery disease (CAD). METHODS: We analyzed 519 patients with CKD (56+/-9 years, 67% men, 67% whites) on maintenance hemodialysis with clinical or scintigraphic evidence of CAD by using coronary angiography. RESULTS: In 230 (44%) patients, coronary angiography revealed significant CAD (lumen reduction > or =70%). Subjects with significant CAD were kept on medical treatment (MT; n=184) or referred for myocardial revascularization (percutaneous transluminal coronary angioplasty/coronary artery bypass graft-intervention; n=30) according to American College of Cardiology/American Heart Association guidelines. In addition, 16 subjects refused intervention and were also followed-up. Event-free survival for patients on MT at 12, 36, and 60 months was 86%, 71%, and 57%, whereas overall survival was 89%, 71%, and 50% in the same period, respectively. Patients who refused intervention had a significantly worse prognosis compared with those who actually underwent intervention (events: hazard ratio=4.50; % confidence interval=1.48-15.10; death: hazard ratio=3.39; % confidence interval 1.41-8.45). CONCLUSIONS: In patients with CKD and significant CAD, MT promotes adequate long-term event-free survival. However, failure to perform a coronary intervention when necessary results in an accentuated increased risk of events and death.