Mohammed R. Essop

Frequency and severity of intravascular hemolysis after left-sided cardiac valve replacement with medtronic hall and St. Jude medical prostheses, and influence of prosthetic type, position, size and number

Intravascular hemolysis occurs often in patients with mechanical heart valve prostheses, but in most cases is of mild degree and subclinical. The severity of hemolysis is reported to be related to the type, position and size of prostheses used, as well as the presence of valve malfunction. Hemolysis was evaluated in 170 patients with St. Jude Medical (SJM) and 80 patients with Medtronic Hall (MH) prostheses, with normal mechanical function. The presence and severity of hemolysis was assessed on the basis of serum lactic dehydrogenase, serum haptoglobin, blood hemoglobin and reticulocyte levels as well as the presence of schistocytes. Overall, patients with SJM prostheses had greater frequency (51.2 vs 18.7%, p < 0.005) and severity (p < 0.005) of hemolysis than patients with MH prostheses, irrespective of position and size. No patient had decompensated anemia. The frequency of hemolysis was similar in both groups with double-valve replacement, whereas severity was greater with SJM than MH prostheses (p < 0.001). The number and position of the prostheses were correlated with severity of hemolysis: Double-valve replacement and mitral position were correlated with greater hemolysis than single-valve replacement (p < 0.01) and aortic position (p < 0.01). Valve size, cardiac rhythm and time from operation did not correlate either with frequency or severity of hemolysis. It is concluded that in normally functioning SJM and MH prostheses: (1) hemolysis is frequent but never severe; (2) SJM demonstrates greater frequency and severity when compared with MH valve; and (3) number, position, but not size, significantly affect the severity of hemolysis.

Effectiveness of Amiodarone and electrical cardioversion for chronic rheumatic atrial fibrillation after mitral valve surgery

Thirty consecutive patients with chronic rheumatic atrial fibrillation (AF) > or = 3 months after successful mitral valve surgery and left atrial diameter < or = 60 mm were treated with oral amiodarone. Protocol included high loading dosages of amiodarone for 4 weeks, and if conversion to sinus rhythm (SR) was not achieved then electrical cardioversion was performed. Patients converted to SR were maintained on low-dose amiodarone for another 4 weeks when treatment was discontinued. Overall, 23 patients (77%) converted to SR after 4 weeks of therapy: 12 (40%) taking amiodarone alone and 11 (37%) with the addition of electrical cardioversion. The duration of AF > 48 months was an adverse factor in the ability to restore SR. Sixteen patients (70%) remained in SR at a mean follow-up of 17 months. The duration of AF < or = 48 months alone or in combination with left atrial diameter < or = 45 mm were the best predictors for long-term maintenance of SR. Thus, short-term amiodarone with or without electrical cardioversion is effective and safe in the treatment of chronic rheumatic AF after mitral valve surgery. The duration of AF and left atrial size can be used to identify patients with successful outcome.

Acute coronary syndromes in treatment-naive black south africans with human immunodeficiency virus infection

BACKGROUNDnHIV patients on protease inhibitors have greater risk of acute coronary syndromes (ACS) but little is known about treatment-naïve patients.nnnMETHODS AND RESULTSnAuthors conducted a prospective single-center study from Soweto, South Africa, comparing the clinical and angiographic features of treatment-naïve HIV positive and negative patients with ACS. Between March 2004 and February 2008, 30 consecutive treatment-naïve HIV patients with ACS were compared to the next HIV-negative patient as a 1:1 control. HIV patients were younger (43 +/- 7 vs. 54 +/- 13, P = 0.004) and, besides smoking (73% vs. 33%, P = 0.002), had fewer risk factors than the control group with less hypertension (23% vs. 77%, P = 0.0001), diabetes (3% vs. 23%, P = 0.05), LDL hyperlipidemia (2.2 +/- 0.9 vs. 3.0 +/- 1.2, P = 0.006), and other coronary risk factors (7% vs. 53%, P = 0.0001). HDL was lower in the HIV group (0.8 +/- 0.3 vs. 1.1 +/- 0.4, P = 0.001). Atherosclerotic burden was lower in the HIV group with more normal infarct-related arteries (47% vs. 13%, P = 0.005) but a higher degree of large thrombus burden (43% vs. 17%, P = 0.02). Stents were used to a similar degree in HIV and control patients (30% vs. 37%, P = 0.78) with more target lesion revascularization in the HIV group (56% vs. 0%, P = 0.008).nnnCONCLUSIONnTreatment-naïve HIV patients with ACS are younger and have fewer traditional risk factors than HIV-negative patients. HIV patients have less atherosclerotic but higher thrombotic burden which may imply a prothrombotic state in the pathogenesis of ACS in these patients.

Isolated Left Ventricular Noncompaction in Sub-Saharan Africa: A Clinical and Echocardiographic Perspective

Background— Isolated left ventricular noncompaction (ILVNC) is a cardiomyopathy caused by intrauterine failure of the myocardium to compact. Common clinical complications are heart failure, arrhythmias, and cardioembolism. A paucity of data exists relating to clinical and echocardiographic features of ILVNC in Africans. Methods and Results— This study is a single-center, prospective case-control study, whereby subjects attending a dedicated cardiomyopathy clinic were screened for and diagnosed with ILVNC, provided they had no other associated structural heart disease and fulfilled all the accompanying echocardiographic criteria: (1) end-systolic ratio of noncompacted layer to compacted layer >2, (2) presence of >3 prominent apical trabeculations, and (3) deep intertrabecular recesses that fill with blood from the ventricular cavity visualized using color Doppler ultrasound. Fifty-four subjects were identified, age 45.4±13.1 years (mean±SD), 95% confidence interval 3.6 to 10.2, 55.6% male, and 63.0% New York Health Association Class II, and prevalence of LVNC in our clinic was 6.9%, 95% confidence interval 3.6 to 10.2. Heart failure because of systolic dysfunction was the most common clinical presentation (53 subjects, 98.1%). Left ventricular end-diastolic diameter was 61.4±7.2 mm (mean±SD) and ejection fraction 26.7±11.9% (mean±SD). Common sites of noncompaction were the apical (100%), midinferior (74.1%), and midlateral (64.8%) walls. Right ventricular noncompaction occurred in 12 subjects (22.2%). Pulmonary hypertension was documented in 45 cases (83.3%). Right ventricular dilation was noted in 40 subjects (74.1%), while right ventricular function was depressed in 32 (59.3%). Tricuspid S was 9.6±2.8 cm/s (mean±SD). No echocardiographic features suggestive of ILVNC were noted in a healthy control group of African descent. Conclusions— ILVNC in patients of African descent can be characterized by biventricular abnormality and pulmonary hypertension, in addition to isolated left-sided abnormality.

Effects of long-acting nifedipine on casual office blood pressure measurements, 24-hour ambulatory blood pressure profiles, exercise parameters and left ventricular mass and function in black patients with mild to moderate systemic hypertension

Thirty-nine black patients with mild to moderate hypertension were treated for 1 year with various long-acting preparations of nifedipine, during which time serial changes in 24-hour ambulatory blood pressure (BP), exercise performance, left ventricular (LV) mass index and LV systolic function were evaluated. Mean 24-hour ambulatory BP decreased from 156 +/- 15/99 +/- 8 to 125 +/- 10/79 +/- 6 mm Hg at 1 year (p less than 0.0001). LV mass index decreased from 130 +/- 40 to 114 +/- 39 g/m2 at 6 weeks (p less than 0.005) and to 95 +/- 32 at 1 year (p less than 0.0001). There was a significant reduction in septal and posterior wall thickness from 11.0 +/- 2.0 to 9.3 +/- 2.0 mm (p less than 0.0001) and from 10.9 +/- 2.0 to 9.3 +/- 2.0 mm (p less than 0.005), respectively. Cardiac index and fractional shortening changed insignificantly from 2.9 +/- 0.7 to 2.9 +/- 0.6 liters/min/m2, and from 35 +/- 5 to 36 +/- 6%, respectively. At 1 year, using a modified Bruce protocol, exercise time increased from 691 +/- 138 to 845 +/- 183 seconds (p less than 0.05); peak exercise and 1 minute post-effort systolic BP decreased from 240 +/- 26 to 200 +/- 21 mm Hg and from 221 +/- 27 to 169 +/- 32 mm Hg (p less than 0.05), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Usefulness of transesophageal echocardiography in the early diagnosis of penetrating stab wounds to the heart

Abstract Cardiac injury by a penetrating instrument is not always limited to the free wall of the heart or the great arteries, but may also involve the interventricular and interatrial septae, as well as the cardiac valves, coronary arteries and conduction system. 1 Rapid and accurate diagnosis is essential in these patients, because mortality is high. 1 The use of color flow Doppler in conjunction with 2-dimensional echocardiographic imaging has greatly expanded our ability for noninvasive investigation of these patients. More recently, transesophageal echocardiography (TEE), with its higher resolution and definition of cardiac structures, has proved to be an excellent imaging modality. In the present study, we summarize our experience with penetrating cardiac injuries and emphasize the role of TEE in the early diagnosis of complex cases.

Left ventricular twist in left ventricular noncompaction.

AIMSnLeft ventricular (LV) twist is an important component of systolic function. The effect of abnormal LV twist on adverse remodelling of the heart in left ventricular noncompaction (LVNC) is unknown. This study used speckle-tracking echocardiography to evaluate LV twist in patients with LVNC and determine whether abnormal LV twist is associated with more adverse LV remodelling.nnnMETHODS AND RESULTSnClinical, echocardiographic, and myocardial deformation characteristics were prospectively compared between 60 subjects diagnosed with LVNC and 59 age-matched healthy controls. Net instantaneous twist was defined as: peak apical rotation minus isochronous basal rotation. Normal rotation during systole was defined based on the 2010 ASE/EAE consensus document. Rigid body rotation (RBR) was determined present if the apex and base moved in the same direction during ejection. Rigid body rotation was found in 32 (53.3%) subjects with LVNC. The 28 subjects with LVNC and normal LV rotation had diminished apical rotation, basal rotation, and net twist compared with normal controls (P < 0.0001). Patients with LVNC and RBR had worse NYHA functional status (P < 0.0001), but similar echocardiographic indices of remodelling, ejection fraction, and strain parameters as those with LVNC and normal LV rotation.nnnCONCLUSIONnLeft ventricular twist is diminished in subjects with LVNC and normal LV rotation. Rigid body rotation occurs in 53.3% of subjects with LVNC and is not associated with more adverse remodelling than subjects with LVNC and normal LV rotation.

Gender-specific brachial artery blood pressure-independent relationship between pulse wave velocity and left ventricular mass index in a group of African ancestry

Aim As it is uncertain whether arterial stiffness is related to left ventricular mass and left ventricle mean wall thickness independent of blood pressure measured at the brachial artery, we aimed to ascertain this effect in never-treated participants with a high prevalence of risk factors for large artery dysfunction. Methods The conventional and ambulatory blood pressure-independent relations between indices of large artery function and either left ventricular mass or mean wall thickness were determined in 309 never-treated randomly recruited South Africans of African ancestry with prevalent risk factors for large artery changes [24% were hypertensive, 63% were overweight/obese, and 17% had diabetes mellitus or abnormal blood glucose control (glycosylated hemoglobin A1c > 6.1%)]. Large artery function was assessed from applanation tonometry performed at the carotid, radial and femoral arteries and central augmentation index and aortic pulse wave velocity (carotid femoral pulse wave velocity) derived from these measures. Left ventricular mass indexed for height2.7 (left ventricular mass index) and mean wall thickness were determined using echocardiography. Results Pulse wave velocity was associated with left ventricular mass index (r = 0.67, P < 0.0001) and mean wall thickness (r = 0.61, P < 0.0001) in women, but not in men (r = 0.04–0.08) (P < 0.0001 for the interaction between pulse wave velocity and gender). On multivariate analysis with appropriate adjustments including either conventional systolic blood pressure, pulse pressure or mean arterial pressure, pulse wave velocity was independently associated with left ventricular mass index (partial r = 0.25, P < 0.005 after adjustments for systolic blood pressure) and with mean wall thickness (partial r = 0.17, P < 0.05 after adjustments for systolic blood pressure) in women, but not in men. With the inclusion of 24-h ambulatory rather than conventional systolic blood pressure, pulse pressure or mean arterial pressure in the regression equation, pulse wave velocity was similarly independently associated with left ventricular mass index (partial r = 0.39, P < 0.001 after adjustments for 24-h systolic blood pressure) and mean wall thickness (partial r = 0.33, P < 0.003 after adjustments for 24-h systolic blood pressure) in women, but not in men. Central augmentation index was not independently associated with left ventricular mass index or mean wall thickness. In women, the contribution of pulse wave velocity to left ventricular mass index or mean wall thickness independent of systolic blood pressure (standardized β-coefficient for left ventricular mass index=0.37 ± 0.13, P < 0.005) was equivalent to the contribution of systolic blood pressure (standardized β-coefficient for left ventricular mass index = 0.38 ± 0.13, P < 0.005). Moreover, after adjusting for clinic or ambulatory systolic blood pressure and other confounders, in women every one standard deviation increase in pulse wave velocity (2.1 m/s) translated into a 4.3 or 6.2 g/m2.7 increase in left ventricular mass index, respectively. Conclusion Arterial stiffness is associated with left ventricular mass index and left ventricle wall thickness independent of conventional or ambulatory blood pressure and additional confounders in a never-treated population sample of women, but not men, of African ancestry with prevalent risk factors for large artery dysfunction.

The Thrombotic Profile of Treatment-Naive HIV-Positive Black South Africans With Acute Coronary Syndromes

Background: Patients with human immunodeficiency virus (HIV) infection on protease inhibitors (PIs) have a heightened risk of arterial thrombosis but little is known about treatment-naive patients. Methods/Results: Prospective study from South Africa comparing thrombotic profiles of HIV-positive and -negative patients with acute coronary syndrome (ACS). A total of 30 treatment-naive HIV-positive patients with ACS were compared to 30 HIV-negative patients with ACS. Patients with HIV were younger; and besides smoking (73% vs 33%) and low high-density lipoprotein (HDL; 0.8 ± 0.3 vs 1.1 ± 0.4), they had fewer risk factors. Thrombophilia was more common in HIV-positive patients with lower protein C (PC; 82 ± 22 vs 108 ± 20) and higher factor VIII levels (201 ± 87 vs 136 ± 45). Patients with HIV had higher frequencies of anticardiolipin (aCL; 47% vs 10%) and antiprothrombin antibodies (87% vs 21%). Conclusion: Treatment-naive HIV-positive patients with ACS are younger, with fewer traditional risk factors but a greater degree of thrombophilia compared with HIV-negative patients.

Rationale and design of the Investigation of the Management of Pericarditis (IMPI) trial: a 2 × 2 factorial randomized double-blind multicenter trial of adjunctive prednisolone and Mycobacterium w immunotherapy in tuberculous pericarditis.

BACKGROUNDnIn spite of antituberculosis chemotherapy, tuberculous (TB) pericarditis causes death or disability in nearly half of those affected. Attenuation of the inflammatory response in TB pericarditis may improve outcome by reducing cardiac tamponade and pericardial constriction, but there is uncertainty as to whether adjunctive immunomodulation with corticosteroids and Mycobacterium w (M. w) can safely reduce mortality and morbidity.nnnOBJECTIVESnThe primary objective of the IMPI Trial is to assess the effectiveness and safety of prednisolone and M. w immunotherapy in reducing the composite outcome of death, constriction, or cardiac tamponade requiring pericardial drainage in 1,400 patients with TB pericardial effusion.nnnDESIGNnThe IMPI trial is a multicenter international randomized double-blind placebo-controlled 2 × 2 factorial study. Eligible patients are randomly assigned to receive oral prednisolone or placebo for 6 weeks and M. w injection or placebo for 3 months. Patients are followed up at weeks 2, 4, and 6 and months 3 and 6 during the intervention period and 6-monthly thereafter for up to 4 years. The primary outcome is the first occurrence of death, pericardial constriction, or cardiac tamponade requiring pericardiocentesis. The secondary outcome is safety of immunomodulatory treatment measured by effect on opportunistic infections (eg, herpes zoster) and malignancy (eg, Kaposi sarcoma) and impact on measures of immunosuppression and the incidence of immune reconstitution disease.nnnCONCLUSIONSnIMPI is the largest trial yet conducted comparing adjunctive immunotherapy in pericarditis. Its results will define the role of adjunctive corticosteroids and M. w immunotherapy in patients with TB pericardial effusion.