Influence of mildly and moderately elevated pulmonary artery systolic pressure on post-renal transplantation survival and graft function.

BACKGROUND: Severe pulmonary hypertension (PH) has been associated with decreased post-kidney transplant survival and increased rate of long-term cardiovascular complications. Despite a high prevalence of PH in patients with end-stage renal disease, data on post-transplant renal allograft survival in recipients with pre-existing mild-to-moderate PH are limited. METHODS: The single-center retrospective study cohort consisted of 192 consecutive (2008-2015) renal transplant recipients with documented pretransplantation transthoracic echocardiogram (TTE) pulmonary artery systolic pressure (PASP). Mean age was 50.9 ± 12.4 years, 36.5% were females, and 81.25% were Caucasians. RESULTS: Elevated PASP ≥ 37 mm Hg was present in 51 patients. Elevated PASP was more common in patients with decreased <50% left ventricular ejection fraction (13.73% vs 3.55%, P = 0.010); otherwise, there were no significant differences in baseline demographic (age, ethnicity, gender, and donor status) and clinical parameters between patients with normal and elevated PASP. Four-year mortality (5.7%) was not significantly affected by elevated PASP. However, elevated PASP was associated with significantly decreased estimated glomerular filtration rate (eGFR) at 1 year (52.26 vs 60.13 mL/min, P = 0.019) and 2 years (51.04 vs 60.28 mL/min, P = 0.006) post-transplant. CONCLUSION: Mild and moderately elevated pre-kidney transplant PASP does not affect 4-year post-transplant mortality or graft loss. However, elevated pretransplant PASP is significantly associated with decreased 1 year and 2 years post-transplant eGFR. Preoperative echocardiographic evaluation for PH may be useful in predicting the probability of short-term renal graft and long-term graft dysfunction in these patients.

Successful percutaneous coronary intervention significantly improves coronary sinus blood flow as assessed by transthoracic echocardiography.

BACKGROUND: Transthoracic echocardiography (TTE) has been used to assess coronary sinus blood flow (CSBF), which reflects total coronary arterial blood flow. Successful angioplasty is expected to improve coronary arterial blood flow. Changes in CSBF after percutaneous coronary intervention (PCI), as assessed by TTE, have not been systematically evaluated. HYPOTHESIS: TTE can be utilized to reflect increased CSBF after a successful, clinically indicated PCI. METHODS: The study cohort included 31 patients (18 females, 62 ± 11 years old) referred for diagnostic cardiac catheterization for suspected coronary artery disease and possible PCI, when clinically indicated. All performed PCIs were successful, with good angiographic outcome. CSBF per cardiac cycle (mL/beat) was measured using transthoracic two-dimensional and Doppler flow imaging as the product of coronary sinus (CS) area and CS flow time-velocity integral. CSBF per minute (mL/min) was calculated as the product of heart rate and CSBF per cardiac cycle. In each patient, CSBF was assessed prospectively, before and after cardiac catheterization with and without clinically indicated PCI. Within- and between-group differences in CSBF before and after PCI were assessed using repeated measures analysis of variance. RESULTS: Technically adequate CSBF measurements were obtained in 24 patients (77%). In patients who did not undergo PCI, there was no significant change in CSBF (278.1 ± 344.1 versus 342.7 ± 248.5, p = 0.36). By contrast, among patients who underwent PCI, CSBF increased significantly (254.3 ± 194.7 versus 618.3 ± 358.5 mL/min, p < 0.01, p-interaction = 0.03). Other hemodynamic and echocardiographic parameters did not change significantly before and after cardiac catheterization in either treatment group. CONCLUSIONS: Transthoracic echocardiographic assessment can be employed to document CSBF changes after angioplasty. Future studies are needed to explore the clinical utility of this noninvasive metric.

Revascularization options in stable coronary artery disease: it is not how to revascularize, it is whether and when to revascularize.

Patients with acute coronary syndromes and severe multivessel or left main coronary artery disease have better outcomes when prompt revascularization is performed in addition to optimal medical therapy (OMT). However, in patients with stable ischemic heart disease, randomized strategy trials have revealed equipoise between initial strategies of OMT alone and OMT plus revascularization. Conducted in diverse stable ischemic heart disease patient populations and throughout the spectrum of atherosclerotic and ischemic burden, the RITA-2, MASS II, COURAGE, BARI 2D and FAME 2 trials demonstrate that OMT alone and OMT plus revascularization yield similar outcomes with respect to mortality and myocardial infarction. What remains unclear is whether there may be one or more subsets of patients with stable ischemic heart disease in whom revascularization may be associated with a reduction in mortality or myocardial infarction, which is to be addressed in the ongoing ISCHEMIA trial.

Accuracy of capsule colonoscopy in detecting colorectal polyps in a screening population.

BACKGROUND & AIMS: Capsule colonoscopy is a minimally invasive imaging method. We measured the accuracy of this technology in detecting polyps 6 mm or larger in an average-risk screening population. METHODS: In a prospective study, asymptomatic subjects (n = 884) underwent capsule colonoscopy followed by conventional colonoscopy (the reference) several weeks later, with an endoscopist blinded to capsule results, at 10 centers in the United States and 6 centers in Israel from June 2011 through April 2012. An unblinded colonoscopy was performed on subjects found to have lesions 6 mm or larger by capsule but not conventional colonoscopy. RESULTS: Among the 884 subjects enrolled, 695 (79%) were included in the analysis of capsule performance for all polyps. There were 77 exclusions (9%) for inadequate cleansing and whole-colon capsule transit time fewer than 40 minutes, 45 exclusions (5%) before capsule ingestion, 15 exclusions (2%) after ingestion and before colonoscopy, and 15 exclusions (2%) for site termination. Capsule colonoscopy identified subjects with 1 or more polyps 6 mm or larger with 81% sensitivity (95% confidence interval [CI], 77%-84%) and 93% specificity (95% CI, 91%-95%), and polyps 10 mm or larger with 80% sensitivity (95% CI, 74%-86%) and 97% specificity (95% CI, 96%-98%). Capsule colonoscopy identified subjects with 1 or more conventional adenomas 6 mm or larger with 88% sensitivity (95% CI, 82%-93) and 82% specificity (95% CI, 80%-83%), and 10 mm or larger with 92% sensitivity (95% CI, 82%-97%) and 95% specificity (95% CI, 94%-95%). Sessile serrated polyps and hyperplastic polyps accounted for 26% and 37%, respectively, of false-negative findings from capsule analyses. CONCLUSIONS: In an average-risk screening population, technically adequate capsule colonoscopy identified individuals with 1 or more conventional adenomas 6 mm or larger with 88% sensitivity and 82% specificity. Capsule performance seems adequate for patients who cannot undergo colonoscopy or who had incomplete colonoscopies. Additional studies are needed to improve capsule detection of serrated lesions. Clinicaltrials.gov number: NCT01372878.

Myocardial performance index correlates with right ventricular ejection fraction measured by nuclear ventriculography.

BACKGROUND: Assessment of right ventricular (RV) ejection fraction (EF) by two-dimensional echocardiography (2D ECHO) is practical but limited because of complex geometry of the RV. Techniques used for accurate measurement of RV EF are invasive or costly. However, derivation of 2D ECHO Doppler parameters to estimate RV function could be useful and inexpensive. METHODS: RV EF measured by nuclear ventriculography was compared with 2D ECHO estimates of myocardial performance index (MPI) and peak tricuspid annular systolic velocity (PTASV). Linear regression analysis and sensitivity analysis were used to analyze the data. RESULTS: RV EF measured by nuclear ventriculography correlated with MPI significantly (r =-0.55, P = 0.005) but not with PTASV (r = 0.09, P = 0.69). Using abnormal RV EF <45% measured by nuclear ventriculography, the sensitivity and specificity for MPI > 0.50 were 45.4% and 100%, respectively. The sensitivity and specificity of PTASV < or = 17.25 cm/sec in detecting abnormal RV EF were 100% and 35.4%. CONCLUSION: MPI greater than 0.50 indicates that RV function is abnormal and a value of PTASV > 17.25 cm/sec indicates normal RV function.

African Americans with LVH demonstrate depressed sensitivity of the coronary microcirculation to stimulated relaxation.

Excess coronary heart disease morbidity and mortality among African Americans remains an important yet unexplained public health problem. We hypothesized that adverse outcome is in part due to intrinsic or acquired abnormalities in coronary endothelial function and vasoreactivity. We compared dose-response curves relating changes in coronary blood flow and epicardial diameter to graded infusions of acetylcholine in 50 African American and 65 white subjects with hypertensive left ventricular hypertrophy (LVH) and normal coronary arteries. These groups were similar for age, body mass index, mean arterial pressure, and indexed left ventricular mass. The same protocol was conducted in 24 normotensive African American and 56 similar white subjects. We found significant depression in the coronary blood flow dose-response curve relation among African Americans when compared with white subjects with similar LVH (P<0.03). Racial differences were observed at all doses of acetylcholine but were less precisely estimated at the highest dose. The same testing among normotensive subjects revealed similar dose-response curves with no significant effect of race. Qualitatively similar results were found with respect to coronary diameter. Adenosine responses, a measure of endothelium-independent function, were similar after partitioning by LVH. Our study demonstrates that there are racial differences in sensitivity of coronary arteries to acetylcholine-stimulated relaxation among those with LVH. These results provide a mechanism whereby racial differences in coronary vasoreactivity might contribute to adverse coronary heart disease outcome among African Americans, a group in whom LVH is prevalent.

The presence of African American race predicts improvement in coronary endothelial function after supplementary L-arginine.

OBJECTIVES: The purpose of our study was to determine if the presence of African American ethnicity modulates improvement in coronary vascular endothelial function after supplementary L-arginine. BACKGROUND: Endothelial dysfunction is an early stage in the development of coronary atherosclerosis and has been implicated in the pathogenesis of hypertension and cardiomyopathy. Amelioration of endothelial dysfunction has been demonstrated in patients with established coronary atherosclerosis or with risk factors in response to infusion of L-arginine, the precursor of nitric oxide. Racial and gender patterns in L-arginine responsiveness have not, heretofore, been studied. METHODS: Invasive testing of coronary artery and microvascular reactivity in response to graded intracoronary infusions of acetylcholine (ACh) +/- L-arginine was carried out in 33 matched pairs of African American and white subjects with no angiographic coronary artery disease. Pairs were matched for age, gender, indexed left ventricular mass, body mass index and low-density lipoprotein cholesterol. RESULTS: In addition to the matching parameters, there were no significant differences in peak coronary blood flow (CBF) response to intracoronary adenosine or in the peak CBF response to ACh before L-arginine infusion. However, absolute percentile improvement in CBF response to ACh infusion after L-arginine, as compared with before, was significantly greater among African Americans as a group (45 +/- 10% vs. 4 +/- 6%, p = 0.0016) and after partitioning by gender. The mechanism of this increase was mediated through further reduction in coronary microvascular resistance. L-arginine infusion also resulted in greater epicardial dilator response after ACh among African Americans. CONCLUSIONS: We conclude that intracoronary infusion of L-arginine provides significantly greater augmentation of endothelium-dependent vascular relaxation in those of African American ethnicity when compared with matched white subjects drawn from a cohort electively referred for coronary angiography. Our findings suggest that there are target populations in which supplementary L-arginine may be of therapeutic benefit in the amelioration of microvascular endothelial dysfunction. In view of the excess prevalence of cardiomyopathy among African Americans, pharmacologic correction of microcirculatory endothelial dysfunction in this group is an important area of further investigation and may ultimately prove to be clinically indicated.