Imad A. Alhaddad

Renal Artery Stenosis in Minority Patients Undergoing Diagnostic Cardiac Catheterization: Prevalence and Risk Factors

Background: Atherosclerotic renal artery stenosis (RAS) is a frequently overlooked clinical entity that can cause progressive renal failure and uncontrolled hypertension. Revascularization of a stenosed renal artery is associated with improved clinical outcomes including the prevention of renal failure. Thus, it is important to recognize all potential candidates for renal artery revascularization. In a general population referred for diagnostic cardiac catheterization, RAS of any severity was found in 30% of patients and significant stenosis (> 50% diameter narrowing) was found in 15% of patients. The number of minority groups is increasing in the US population, and RAS in this population is not well investigated. Our purpose was to determine the prevalence and risk factors associated with RAS in minority patients referred for diagnostic cardiac catheterization. Methods: Abdominal aortography was performed in 171 consecutive minority patients referred for diagnostic cardiac catheterization (hispanics = 115, African Americans = 56). The association of clinical and angiographic variables with RAS was examined using univariate and multivariate logistic regression analyses. Results: Renal artery stenosis of any severity was identified in 13.5% of patients (unilateral 7.7%, bilateral 5.8%). Significant RAS was found in 7.7% of patients (unilateral 4.8%, bilateral 2.9%). Independent predictors of RAS included age (mean ±SD, 68 ±0 vs 57 ± yr, P < 0.001, for patients with vs without RAS), coronary artery disease, and elevated serum creatinine levels (> 115,umolVL). Race/ethnicity (hispanics vs African Americans), sex, smoking, congestive heart failure, diabetes mellitus, peripheral vascular disease, and hyper-tension were not independent predictors. Conclusions: Renal artery stenosis in minority patients undergoing diagnostic cardiac catheterization is less common than reported in white patients, is similar in hispanics and African Americans, and is similar in women and men. The clinical and angiographic features are helpful in predicting its presence.

Benefits of late coronary artery reperfusion on infarct expansion progressively diminish over time: relation to viable islets of myocytes within the scar.

To define the time limit and mechanism of the effects of late coronary artery reperfusion on infarct expansion, rats were randomized into one of four groups: permanent left coronary artery occlusion; and 2, 8, and 16 hours of left coronary artery occlusion followed by reperfusion. Two weeks after coronary occlusion, morphometric and histologic analyses were performed. Benefits of late reperfusion on infarct expansion progressively diminished after increasingly long periods of coronary occlusion and were minimal but present after 16 hours of coronary occlusion. The extent of the benefits of late reperfusion on infarct expansion were related to preservation and hypertrophy of small islets of still viable myocytes located mainly in the subepicardium of the scar.

Contemporary outpatient percutaneous coronary intervention: feasible and safe.

BackgroundOutpatient percutaneous coronary intervention (PCI) is safe in selected low risk population. Drug eluting stents (DESs) have expanded the indications of PCI to include more complex anatomies and multivessel disease. HypothesisOutpatient PCI strategy (transfemoral access with manual sheath removal) is feasible and safe in the era wide utilization of DES. MethodsWe enrolled 150 consecutive patients (males=82%, smokers=43%, diabetics=40%) referred for elective or semielective PCI. All patients were treated in the catheterization laboratory short-stay area. ResultsProcedural success was achieved in 97% of the cases. DESs were used in 88% of patients. Seventy-one percent of patients had single vessel PCI and 29% had multivessel PCI. The majority (n=124, 83%) was discharged within 10 h post-PCI (outpatient group) and 26 patients (17%) were admitted to the hospital for longer observation (hospital group). Of the outpatient group; there were no in-hospital deaths, myocardial infarctions or repeat revascularization. Two patients developed small femoral access site hematoma (treated conservatively). No readmissions or complications within 24 h after discharge were found. Administration of glycoprotein inhibitors and type-C lesion were independent predictors of failed same-day discharge. Conclusion(i) Transfemoral outpatient PCI with manual sheath removal is feasible and safe in the era of DES. (ii) The majority of patients undergoing single or multivessel PCI can be discharged within 10 h postprocedure. (iii) Out-patient PCI has the potential of decreasing cost and improving hospital bed utilization.

Early angiotensin converting enzyme inhibitor therapy after experimental myocardial infarction prevents left ventricular dilation by reducing infarct expansion: a possible mechanism of clinical benefits.

ObjectiveTo examine the effects of early angiotensin-converting enzyme (ACE) inhibitor therapy after myocardial infarction on infarct expansion in an experimental rat model. BackgroundACE inhibitor therapy within 24 h of acute myocardial infarction (AMI) reduces mortality by unknown mechanism(s). MethodsRats underwent permanent coronary artery occlusion. A treated group received enalapril (1.9 ± 0.2 mg/kg) daily in drinking water beginning 2 h after coronary artery occlusion, a time too late to reduce infarct size. Rats were sacrificed 2 days or 2 weeks after myocardial infarction. Hearts were arrested and fixed at a constant pressure, then sectioned and photographed for morphometric analysis. ResultsInfarcts in the control group expanded between 2 days and 2 weeks after myocardial infarction (expansion index 0.7 ± 0.1 versus 2.5 ± 0.4, P < 0.05). However, infarct expansion remained unchanged in the enalapril group between 2 days and 2 weeks after myocardial infarction (expansion index 0.8 ± 0.1 versus 1.3 ± 0.1, NS). Two weeks after myocardial infarction, the enalapril group had fewer expanded infarcts than the control group (expansion index 1.3 ± 0.1 versus 2.5 ± 0.4, P < 0.05). While left ventricular volume increased in the control group between 2 days and 2 weeks after myocardial infarction (0.17 ± 0.01 ml versus 0.36 ± 0.03 ml, P < 0.05), it remained constant in the enalapril group (0.22 ± 0.02 ml versus 0.25 ± 0.03 ml, NS). Two weeks after myocardial infarction, the left ventricles were larger in the control group than in the enalapril group (0.36 ± 0.03 ml versus 0.25 ± 0.03 ml, P < 0.05). ConclusionsTreatment with enalapril initiated 2 h after AMI prevented left ventricular dilation by limiting infarct expansion. This may explain the mechanism by which ACE inhibitor therapy started within 24 h of an AMI improves survival 5–6 weeks after infarction.

Triggers and the onset of acute myocardial infarction.

The onset of acute myocardial infarction (AMI) is a complex interplay of internal circadian factors and external physical and emotional triggers. These interactions may lead to rupture of an often nonocclusive vulnerable atherosclerotic coronary plaque with subsequent formation of an occlusive thrombus. The onset of AMI has a distinct pattern, with peak incidence within the first few hours after awakening, on certain days of the week, and in the winter months. Physical and emotional stresses are important triggers of acute cardiovascular events including AMI. Triggering events, internal changes, and external factors vary among different geographical, environmental, and ethnic regions. Life-style changes, pharmacotherapy, and psychologic interventions may potentially modify the response to, and protect against the effects of triggering events.

Effect of ColchiciNe on the InciDence of Atrial Fibrillation in Open Heart Surgery Patients: END-AF Trial

BACKGROUND Atrial fibrillation (AF) is a common arrhythmia in patients undergoing cardiac surgery and may result in significant morbidity and increased hospital stay. This study was conducted to determine if colchicine administered preoperatively to patients undergoing cardiac surgery and continued during hospitalization is effective in reducing the incidence of postoperative AF. METHODS In this multicenter prospective randomized open-label study, consecutive patients with no history of AF and scheduled to undergo elective cardiac surgery (n = 360) were randomized to colchicine (n = 179) or no-colchicine (n = 181). Main exclusion criteria were history of AF or supraventricular arrhythmias or absence of sinus rhythm at enrolment, and contraindications to colchicine. Colchicine was orally administered 12 to 24 hours preoperatively and continued until hospital discharge. The primary efficacy end point was documented AF lasting more than 5 minutes. Safety end point was colchicine adverse effects. RESULTS In-hospital mortality was 3.3%. The primary end point of AF occurred in 63 patients (17.5%): 26 (14.5%) in the colchicine group and 37 (20.5%) in the no-colchicine group (relative risk reduction 29.3% [P = .14]). Diarrhea occurred in 54 patients, 44 (24.6%) on colchicine and 10 (5.5%) on no-colchicine (P < .001). Diarrhea led to discontinuation of colchicine in 23 (52%) of the 44 patients. CONCLUSION Colchicine administered preoperatively to patients undergoing cardiac surgery and continued until hospital discharge failed to significantly reduce the incidence of early postoperative AF. Diarrhea was the most common adverse effect of colchicine leading to its discontinuation in more than half of the patients with this adverse effect.

Outcomes following implantation of the Biolimus A9-eluting BioMatrix coronary stent: Primary analysis of the e-BioMatrix registry.

To assess the safety and efficacy of Biolimus A9‐eluting stents (BES, BioMatrix™ and BioMatrix Flex™) in routine clinical practice.

Treatment adherence and quality of life in patients on antihypertensive medications in a Middle Eastern population: adherence

Background Poor adherence to antihypertensive treatment remains a clinical challenge worldwide. The objectives of this study were to assess the adherence level to antihypertensive treatment and to identify its associated factors in a sample of hypertensive patients in Lebanon and Jordan. Methods We conducted an observational study between May 2011 and September 2012. A total of 1,470 eligible hypertensive patients were enrolled in our study and followed up for a period of 6 months. Data were collected regarding sociodemographic, health behavior, and hypertension-related characteristics. The adherence to treatment and the quality of life were self-reported using the Morisky, Green & Levine Scale and the Hypertension Quality of Life Questionnaire. Results Our results revealed that 55.9 % of the patients were adherent to their antihypertensive medication. Older age was associated with better adherence, whereas being divorced or widowed, having a poorer quality of life, and being classified as having stage 1 or 2 hypertension at the end of the study were all associated with poorer adherence. Conclusion Efforts should be exerted on all levels in order to increase the adherence to anti-hypertensive treatment through the implementation of educational campaigns.

Early angiotensin converting enzyme inhibitor therapy enhances the benefits of late coronary artery reperfusion on infarct expansion.

BackgroundIndividually, both late reperfusion and early angiotensin converting enzyme (ACE) inhibitor treatment prevent infarct expansion after acute myocardial infarction. ObjectiveTo examine the effect and mechanism of early post‐myocardial infarction ACE inhibitor treatment, when used in combination with late coronary artery reperfusion, on infarct expansion. MethodsSprague–Dawley rats underwent 8 h of coronary occlusion followed by permanent reperfusion. The treatment group received enalapril, started 1 h after coronary occlusion and continued for 13 days. A control group received placebo. Two weeks after acute myocardial infarction, hemodynamic, morphometric and histologic analyses were performed. ResultsHemodynamic parameters were similar in both groups (P  = NS). Infarct size was similar in the ACE inhibitor and placebo treatment groups (44 ± 4% compared with 39 ± 4%, P  = NS). Septal thickness was also similar in the two groups (2.8 ± 0.3 mm compared with 2.7 ± 0.3 mm, P = NS). The ACE inhibitor‐treated group had thicker infarcts than those in the placebo‐treated group (0.93 ± 0.07 mm compared with 0.76 ± 0.04 mm, P  < 0.05) and these infarcts were less expanded (expansion index 1.17 ± 0.12 compared with 1.57 ± 0.12, P  < 0.05). ACE inhibitor treatment was associated with hypertrophy of viable myocytes within the scar compared with placebo treatment (cell diameter 11.1 ± 0.5 m compared with 8.9 ± 0.4 m, P  < 0.01). ConclusionsEarly post‐myocardial infarction ACE inhibitor treatment enhances the benefits of late coronary reperfusion on infarct expansion. The benefits may be related to hypertrophy of still‐viable myocytes within the infarcted zone.

Pulmonary artery agenesis associated with coronary collaterals among adults.

BackgroundUnilateral agenesis of the pulmonary artery is a rare congenital anomaly, which commonly involves the right side. Cases are associated with systemic collaterals, that may also arise from the coronary arteries.Case presentationTwo adult patients are presented with exertional dyspnea. Investigations revealed a right pulmonary artery agenesis associated with collaterals from right coronary artery. The implication of such an anomaly was different among both patients due to associated systemic collaterals and congenital heart lesions. Both patients were treated medically to control pulmonary artery pressure.ConclusionsAdult patients with pulmonary artery agenesis have variable presentations and hemodynamic conditions. The presence of associated congenital heart disease and extensive systemic collaterals play a major role in hemodynamics. The association of coronary collaterals is rare and its implication varies from no effect to ischemic manifestations and myocardial infarction.