Elif Sade

Evaluation of coronary microvascular function in patients with end-stage renal disease, and renal allograft recipients.

BACKGROUND Approximately half of all deaths in patients with end-stage renal disease (ESRD) are due to cardiovascular diseases. Although renal transplant improves survival and quality of life in these patients, cardiovascular events significantly affect survival. We sought to evaluate coronary flow reserve (CFR), an indicator of coronary microvascular function, in patients with ESRD and in patients with a functioning kidney graft. METHODS Eighty-six patients (30 with ESRD, 30 with a functioning renal allograft, and 26 controls) free of coronary artery disease or diabetes mellitus were included. Transthoracic Doppler echocardiography was used to measure coronary peak flow velocities at baseline and after dipyridamole infusion. CFR was calculated as the ratio of hyperemic to baseline diastolic peak flow velocities and was compared among the groups. RESULTS The mean age of the study population was 36.1+/-7.3 years. No between-group differences were found regarding age, sex, or prevalences of traditional coronary risk factors other than hypertension. Compared with the renal transplant and control groups, the ESRD group had significantly lower mean CFR values. On multivariate regression analysis, serum levels of creatinine, age, and diastolic dysfunction were independent predictors of CFR. CONCLUSIONS CFR is impaired in patients with ESRD suggesting that coronary microvascular dysfunction, an early finding of atherosclerosis, is evident in these patients. Although associated with a decreased CFR compared with controls, renal transplant on the other hand seems to have a favorable effect on coronary microvascular function.

Coronary microvascular function in patients with isolated systolic and combined systolic/diastolic hypertension.

J Clin Hypertens (Greenwich). 2012;14:871–876. ©2012 Wiley Periodicals, Inc.

Comparison of Tissue Doppler Echocardiography Parameters in Patients With End-Stage Renal Disease and Renal Transplant Recipients

BACKGROUND Tissue Doppler echocardiography has been introduced as a useful tool to assess systolic myocardial function. In this study we sought to compare patients with end-stage renal disease (ESRD), with renal transplantations and control subjects with regard to tissue Doppler parameters. METHODS Thirty recipients with functional grafts of overall mean age 36 +/- 7 years included 24 men. An equal number of patients with ESRD of overall mean age 35 +/- 7 years included 20 men. A third cohort was comprised of 20 age- and gender matched control subjects. Tissue Doppler imaging from the septal and lateral mitral annulus of the left ventricle and free wall of the right ventricle was performed from a 4-chamber view. RESULTS Mean systolic and diastolic blood pressures were similar among the groups during imaging. Peak systolic velocity (S wave) at the septal annulus was similar in control subjects and recipients. S waves were significantly lower among ESRD patients compared with recipients (10.3 +/- 2.1 vs 12.0 +/- 2.5 cm/s, P = .04, respectively). Isovolumic contraction velocity of the septum and the right ventricular wall were significantly lower in ESRD patients than recipients or controls: 10.2 +/- 2.6 vs 12.5 +/- 2.8 vs 11.4 +/- 1.8 cm/s for septal wall (P = .008) and 13.9 +/- 3.6 vs 17.9 +/- 5.1 vs 16.8 +/- 5.8, for right ventricle (P = .01). CONCLUSION Systolic indices of tissue Doppler echocardiography in recipients demonstrated similar values as control subjects and increased values compared with ESRD patients. These results suggested improvement in systolic myocardial function following renal transplantation.

Analysis of right ventricle function with strain imaging before and after pulmonary valve replacement

BACKGROUND Pulmonary valve insufficiency may develop after surgical treatment of tetralogy of Fallot (ToF). Severe pulmonary valve insufficiency may result in right ventricular dysfunction. We aimed to compare cardiac magnetic resonance (CMR), with echocardiography. METHODS Patients who developed severe pulmonary valve insufficiency after total correction for ToF, were included in the study. CMR was used to measure end-diastolic, end-systolic volumes and ejection fraction of the right ventricle before and 6 months after replacement, and echocar-diographic strain imaging was obtained before, and 1, 3, and 6 months after replacement. RESULTS There were significant differences between pre- and post-replacement QRS durations, and right ventricle end-diastolic and end-systolic volumes measured with CMR (p < 0.05). However, right ventricular ejection fraction (RVEF) did not change. Therefore, CMR determined that right ventricle size and volume increased, and right ventricular function deteriorated before replacement. After replacement, no significant improvement was seen in RVEF. Lower-than-normal right ventricle strain and strain rate before replacement indicated that healthy and dysfunctional myocardium could be differentiated by this method. Pre-replacement strain and strain rate of asymptomatic and symptomatic patients were similar. Strain and strain rate values increased 6 months after replacement (p < 0.05). CONCLUSIONS We suppose that increased experience with strain imaging, and further studies on a larger patient group with a longer follow-up period would show that this method is quite advantageous, and it will take its place in the literature as a non-invasive technique that may be used instead of magnetic resonance.

The Prevalence and Course of Pulmonary Hypertension and Right Ventricular Dysfunction in Patients Undergoing Orthotopic Heart Transplantation

BACKGROUND Pulmonary hypertension (PHT) and right ventricular (RV) dysfunction are among the commonly observed and potentially serious complications following heart transplantation. RV dysfunction is reported to occur in as much as half of these patients. In this study, the authors sought to examine the prevalence and the course of these prognostically important complications. METHODS The records of 30 patients who had undergone orthotopic heart transplantation at our center were examined. Demographic and clinical variables were noted; RV dysfunction, pulmonary artery pressure on Doppler echocardiographic examination, and catheter findings were recorded. RESULTS The mean age of the study population was 31.3 years. On preoperative assessment, PHT was present in 21 (70%) patients. The average value of systolic pulmonary artery pressure was 44.5 ± 5.9 mm Hg. The mean value of pulmonary vascular resistance was 3.3 ± 1.8 hybrid reference unit (HRU). RV dysfunction was detected on postoperative assessment in 17 (56.7%) patients. The mean ischemia time was 216 ± 77 minutes; in 3 cases it exceeded 5 hours but in none of the cases did it reach 6 hours. Rejection was detected in 14 (46.7%) patients. Most of the patients received inotropic agents in the early postoperative period. When compared with preoperative values, on follow up at the end of the first year, a significant decrease in pulmonary artery pressure was observed (47.4 ± 4.8 vs 38.5 ± 7.5 mm Hg; P = .03), and the ratio of patients experiencing RV dysfunction decreased to 16.6% (n = 5). CONCLUSION The findings of this study indicate that RV dysfunction and PHT are common complications following heart transplantation and improve with appropriate management over time with monitoring.