Mikhail Torosoff

Incidence of Contrast-Induced Nephropathy in Patients With Chronic Renal Insufficiency Undergoing Multidetector Computed Tomographic Angiography Treated With Preventive Measures

Contrast-induced nephropathy (CIN) is associated with adverse outcomes. Strategies for its prevention have been evaluated for patients undergoing invasive coronary and peripheral angiography, including treatment with N-acetylcysteine, sodium bicarbonate, and use of iso-osmolar nonionic contrast. Recently, multidetector computed tomographic angiography (MDCTA) of the coronary and peripheral arteries has been introduced as an accurate method for assessing vascular stenosis and has been widely adopted for assessment of outpatients with suspected coronary artery disease or peripheral arterial disease. To date, the incidence of CIN in outpatients with chronic renal insufficiency (CRI) treated with CIN-preventive strategies undergoing MDCTA remains unknown. Thus, we evaluated the incidence of CIN in outpatients with CRI (creatinine 1.5 to 2.5 mg/dl) undergoing MDCTA using CIN-preventive measures; 400 patients with CRI (78.5% men, mean age 76 years, 41% with diabetes) underwent MDCTA with iodixanol for detection of coronary artery disease or peripheral arterial disease (mean contrast volume 101 cc). CIN was defined as a nonallergic creatinine increase of >0.5 mg/dl. Creatinine levels were obtained before and 3 to 5 days after MDCTA; the average creatinine levels were 1.80 mg/dl and 1.75 mg/dl, respectively (p = NS), with an average change of -0.03 mg/dl. In the study cohort, only 7 patients (1.75%) experienced a creatinine increase >0.5 mg/dl, satisfying the definition of CIN. In conclusion, multivariate analysis, diabetes was the only predictor for CIN (odds ratio 5.9, 95% confidence interval 1.0 to 33.3, p = 0.045). No patient required hemodialysis. In conclusion, in patients with CRI undergoing MDCTA and receiving CIN-preventive measures, the incidence of CIN is low.

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.

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 ≤ 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

Abstract—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.

Patient Selection and Outcomes of Transfemoral Transcatheter Aortic Valve Replacement Performed with Monitored Anesthesia Care versus General Anesthesia

OBJECTIVE The aim of this study was to compare outcomes of monitored anesthesia care (MAC) versus general anesthesia (GA) for transfemoral transcatheter aortic valve replacement (TF-TAVR) and to describe a selection process for the administration of MAC. DESIGN Retrospective analysis of patients who underwent TF-TAVR under MAC or GA. SETTING Department of Cardiac Anesthesia, Albany Medical Center, a tertiary university hospital. PARTICIPANTS Patients selected for TF-TAVR. INTERVENTIONS Patients were divided into those who underwent MAC and those who underwent GA. MEASUREMENTS AND MAIN RESULTS The study comprised 104 consecutive patients (55% male, mean age 83 years) who underwent TF-TAVR under MAC (n = 60) or GA (n = 37) from 2014 to 2015. Seven patients were converted from MAC to GA and were omitted from analysis. There was no statistically significant difference between 30-day mortality and complications between the 2 groups. The MAC group had a significantly shorter median intensive care unit length of stay (48 h v 74 h, p = 0.0002). The MAC group also demonstrated reduced procedural time (45.5 min v 62 min, p = 0.003); operating room time (111 min v 153 min, p = <0.001); and fluoroscopy time (650 s v 690 s, p = 0.03). CONCLUSIONS Patient selection for TF-TAVR with MAC can be formalized and implemented successfully. MAC allows for the minimizing of patient exposure to unnecessary interventions and improving resource utilization in suitable TAVR patients. Selection requires a multidisciplinary clinical decision-making process. MAC demonstrates good outcomes compared with GA, yet it is important to have a cardiac anesthesiologist present in the event of emergency conversion to GA.

Postoperative hyperbilirubinemia is an independent predictor of longterm outcomes after cardiopulmonary bypass.

BACKGROUND Two decade-old studies of cardiopulmonary bypass (CPB) patients documented a 25% to 35% incidence of postoperative hyperbilirubinemia, associated with increased in-hospital morbidity and mortality. Longterm consequences of this complication are unknown. STUDY DESIGN Medical records of CPB patients were reviewed. Mortality was ascertained through the National Death Index. Proportional hazards determined important factors in post-CPB survival. Logistic regression delineated predictors of hyperbilirubinemia. Kaplan-Meier and Mantel-Cox log-rank survival analyses compared hyperbilirubinemia groups. RESULTS Bilirubin levels were followed in 826 (59.7%) patients. Bilirubin was normal in 570 (69.0%) patients (group 1), it was 1.4 to 2.8 mg/dL in 184 (22.3%) patients (group 2), and it exceeded 2.8 mg/dL in 72 (8.7%) patients (group 3). Elevated bilirubin was associated with decreased body mass index, congestive heart failure, heparin before operation, postoperative transfusion requirement, bleeding, and renal failure. In-hospital mortality was 4.3% in group 2 and 25.0% in group 3, compared with 0.9% in group 1 (p<0.001). Two-year crude survival was 95.8% in group 1, 84.8% in group 2, and 62.5% in group 3 (p<0.001). Multivariable predictors of longterm mortality were older age, history of stroke, emergency operation, increased duration of cardiopulmonary bypass, respiratory failure, and elevated bilirubin. Compared with survival in group 1, there was a 1.7-fold decrease in group 2 2-year survival (95% CI 0.9 to 3.0; p=0.09) and a 3.8-fold decrease in group 3 survival (95% CI 2.0 to 7.2; p<0.001). CONCLUSIONS Postoperative bilirubin elevation in CPB patients is common and deadly. The predictive power of hyperbilirubinemia is similar to that of respiratory failure. The cause of postbypass hyperbilirubinemia is unknown and is probably multifactorial. Additional prospective studies are warranted.

Effect of Comorbidities and Medications on Left Ventricular Mass Regression After Bariatric Surgery

J Clin Hypertens (Greenwich). 2010;12:223–227. ©2010 Wiley Periodicals, Inc.

Phenytoin as an effective treatment for polymorphic ventricular tachycardia due to QT prolongation in a patient with multiple drug intolerances

We present a case of a 69-year-old woman presenting with polymorphic ventricular tachycardia caused by QT prolongation. Owing to known intolerances to a majority of antiarrhythmic medications, one remaining option was to initiate phenytoin. Phenytoin’s narrow therapeutic window, multiple drug interactions and side effect profile make it an infrequently used antiarrhythmic. It is, however, a potent antiarrhythmic agent, which may be useful in treatment of ventricular tachycardia, especially in patients with multiple drug intolerances.

Disseminated Intravascular Coagulation with Congestive Heart Failure and Left Ventricular Thrombus: A Case Report with Literature Review of 7 Cases

Patient: Male, 55 Final Diagnosis: Disseminated intravascular coagulation Symptoms: Leg pain • short of breath • swelling legs Medication: — Clinical Procedure: — Specialty: Cardiology Objective: Unusual clinical course Background: Coagulation abnormalities can accompany acute congestive heart failure (CHF). However, disseminated intravascular coagulation (DIC) is rarely documented in such patients. DIC is characterized by generalized excessive activation of coagulation pathways followed by their depletion with secondary activation of anticoagulation and fibrinolysis. Treatment of the cause is an integral part of management of DIC; thus, recognition of the cause is critical. Case Report: A 55-year-old previously healthy man presented with breathlessness, swelling of both legs, and left leg pain. His physical exam result was consistent with decompensated heart failure. Further testing revealed multiple deep venous thrombi in the upper and lower extremities, arterial occlusion in the left popliteal artery, and an unusual cyst-like left ventricular thrombus. His laboratory evaluation was consistent with severe acute DIC. The patient was managed aggressively with diuretics, transfusions of platelets, and cryoprecipitate and was subsequently anticoagulated. His platelet count and coagulation parameters normalized and coronary angiography did not reveal any obstructive lesions. On day 22, an echocardiogram revealed and MRI confirmed that the intracardiac thrombus had disappeared. He underwent revascularization of the left leg and was successfully discharged from the hospital. Conclusions: Severe biventricular non-ischemic cardiac dysfunction with intra-cardiac thrombi should be considered in patients presenting with DIC. In addition to anticoagulation, treatment of underlying heart failure is critical in such cases.

Improving outcomes in diastolic heart failure. Techniques to evaluate underlying causes and target therapy.

PREVIEW Abnormal diastolic function is a common cause of clinical heart failure, particularly among elderly patients. Through early diagnosis and careful management of diastolic dysfunction, these patients can expect improved functional capacity and, in some cases, a favorable long-term outcome. In this article, Drs Torosoff and Philbin discuss how to confirm the diagnosis of diastolic heart failure through objective testing. Current approaches to the treatment of symptoms, including reduction of intravascular volume, heart rate control, and elimination of precipitating factors, are also presented.