Comparison of dobutamine stress and atropine exercise stress test myocardial perfusion spect in patients with poor exercise capacity

Exercise stress test [E] is the main diagnostic stress modality used with myocardial perfusion SPECT [MPS]. However, its usefulness and accuracy depends on patient's [pt] ability to achieve target heart rate [THR], limiting its utility in pt with poor exercise capacity. We sought to study the safety and feasibility of atropine administration during exercise myocardial perfusion study [EMPS] as compared to standard dobutamine MPS. Thirty patients aged 51.4 +/- 8.3 years; 80% males referred for a diagnostic MPS study and failed to achieve their THR on E. Patients were divided in to 2 groups [G]; G I 15 pts continued E and atropine was administered in doses of 0.5 mg /min until THR achieved or ischemic ECG changes or a maximum dose of 2 mg. GII 15 patients were subjected to dobutamine MPS from the start. There was no significant difference between the two groups regarding pretest likelihood of ischemia, resting heart rate, systolic and diastolic blood pressures. All pts in GI reached THR after atropine injection. GII experienced more side effects [40% vs 0%, p=0.017]; varying from chest pain 33%, headache 6.7%, nausea and vomiting 6.7%. No difference was found in the frequency of ECG changes [37% vs 47%] or frequency of positive MPS [87% vs 80%]. Use of atropine as an adjunct to standard EMPS in pts with poor exercise capacity allows them to achieve THR and can help decrease the number of inconclusive tests. Atropine EMPS is better tolerated by than dobutamine MPS

Non-invasive assessment of peripheral arterial disease in asymptomatic diabetic patients: Whom should we screen?

Diabetes mellitus is a major risk factor for cardiovascular morbidity and mortality. This condition increases the risk of developing coronary, cerebrovascular and peripheral arterial disease [PAD] up to 4 fold. It has been reported that more than half of those with PAD are asymptomatic or have atypical symptoms. Peripheral arterial disease [PAD] increases the risk of heart attack, stroke, amputation and death, hence early identification and treatment are crucial. The aim of this work was to assess the value of non invasive imaging using echo-doppler technique to detect peripheral arterial disease in diabetic and non-diabetic Egyptians. This study was conducted on forty patients admitted to Cardiology Department, Alexandria University suffering from anginal chest pain for evaluation of their chest pain, they were divided into two groups - Twenty diabetics suffering from type II diabetes, and twenty non diabetics. The two groups are matched as regard age and sex, there is significant increase in serum cholesterol, triglycerides, carotid intimal thickness in diabetic group there is marked increase in Carfem index in diabetic group but with no significant difference in ankle brachial index. As regards coronary angiography, most of diabetic patients [85%] are suffering from multi-vessels coronary artery disease. Non invasive measurements of atherosclerosis [Carotid and Carfem index] are of significant evidence in diabetic patients. Carfem index is a major predictor of coronary artery in diabetic patients. The ankle brachial pressure index was less sensistive than intimal and medial thickness of carotid and femoral arteries in the detection of early stages of atherosclerosis

Early results of combined coronary artery by-pass grafting and valve replacement

In the era of continously evolving cardiac interventions, the profile of patients referred for coronary artery bypass grafting [CABG] is changing to include older patients with concomitant diseases and co-morbidities. Studies on the results of a specific type of valve pathology operation in combination with CABG are few. This study conducted on 29 consecutive patients who underwent combined CABG and valve operations between January 2002 and December 2006. Follow-up for survival and events continued six months after discharge. All patients underwent cardiac catheterization within 3 months before operation Patients age ranged from 30-72 years, with a mean of 56.3 +/- 9.64 years, of these patients, 21 patients [72.4%] were males, whereas 8 patients [27.6%] were females. They underwent a combination of CABG with either isolated aortic valve replacement [n - 16], isolated mitral valve replacement [n = 9], or double valve replacement [n = 4]. LAD was grafted in 23 patients, RCA was grafted in twelve patients, OM was grafted in ten patients and saphenous vein was used to graft the diagonal branch of the LAD in two patients. It was found that sex, age, the duration of aortic cross clamping, and arrythmias specially atrial fibrillation and heart block are important determinants of early post-operative events suggesting restriction of the number of distal anastomosis to shorten the aortic cross-clamp

Early use of clopidogrel after coronary artery by-pass grafting

A better preserved hemostasis increases the risk of thrombosis, which is of particular importance for the patency of coronary anastomosis. Thromboembolic complications seem to be more frequent following off-pump coronary artery by-pass [OP CAB] than after conventional coronary Artery by-pass grafting [CABG], it is not known whether the conventional antiplatelet treatment, as established for on-pump procedures, is optimal for OPCAB-patients. Clopidogrel is a potent platelet aggregation inhibitor, that has gained widespread acceptance for the treatment of acute coronary syndromes and as an adjunct to percutaneous coronary intervention. Is to detect safety and efficacy of administration of clopidogrel early post-operative. Seventy five patients who underwent primary isolated CABG in Alexandria Forty two patients received dopidogrel after OPCAB or conventional on pump coronary artery bypass grafting according to surgeon's decision. The rest of patients didn't receive dopidogrel. Patients were divided into two groups, dopidogrel group [42 patients 56%] had received dopidogrel post-operatively, the no-clopidogrel group [33patients 44%] didn't receive dopidogrel. Post-operative bleeding, chest tube drainage, blood transfusion was detected. In the dopidogrel group, 38 patients [90.5%] received blood transfusions, and the mean number of packed red blood cells transfused during hospitalization was 3.8 +/- 2.2 units. In the second group, 29 patients [87.8%] received blood transfusions, and the mean number of packed red blood cells transfused was 3.5 +/- 2.6 units. No significant differences were noted in the development of early postoperative [within 30 days] pleural effusions requiring thoracentesis. This study documents the safety of early dopidogrel administration after coronary revascularization when administered according to a defined postoperative protocol. Major gastrointestinal bleeding is considered of most frequent risk and needs to be considered

Soluble tumor necrosis factor receptor -2 in acute coronary heart diseases

The aim of this study was to evaluate the impact of soluble tumor necrosis factor receptor -2 in acute coronary heart diseases. This prospective study had been carried on 30 patients with acute coronary heart diseases [group I] admitted consecutively in the critical care medicine department at Alexandria main university hospital. Demographic data and medical history had been taken. Thorough clinical examination, Troponin, CKMB, ECG, x ray chest and echocardiography had been done for each patient on admission. In addition, samples of plasma had been taken from each patient and also, from 10 healthy volunteers of matched age and sex [control group] [group II] to determine plasma level of soluble tumor necrosis factor receptor -2 [sTNFR-2] by ELISA test. Plasma level of sTNFR-2 in group [I] was significantly higher than the group [II], [mean +/- SD was 15.315 +/- 8.909 versus 5.03 +/- 2.01ng/ml respectively, t=5.22. p = 0.0001*]. It was found non significant positive correlation between both ejection fraction [EF] and fraction shorting [FS] [left ventricular systolic function] and sTNFR-2, [r=0.121, p=0.526, r=0.293 and p=0.116 respectively]. Non significant, negative correlation was found between both early filling left ventricle/late filling left ventricle [E/A ratio] [left ventricular diastolic function] and mitral valve regurgitation [MR] and sTNFR-2 [r=- 0.108, p=0.569, r=-0.320 and p=0.085 respectively]. A negative significant correlation was found between wall motion score index [WMSI] and sTNFR-2 [r=-0.419, p=0.021*]. Measurement of sTNFR-2 may be of value in evaluation of the TNF system in acute coronary heart diseases. sTNFR-2 is increased in acute coronary heart diseases and may modulate the in vitro cytotoxicity of TNF. In this work, it is not clear whether the elevation of sTNFR-2 in acute coronary heart diseases is due to an actual increase or to a reduced breakdown or elimination of these receptors. Further explorations are needed to more precisely define the meaning, molecular basis, and interaction ofsTNFR-2 and TNF

Diagnostic accuracy of dobutamine thallium-201 tomography in hypertensive patients with left ventricular hypertrophy

The noninvasive prognostic assessment of coronary artery disease [CAD] in hypertensive patients with left ventricular hypertrophy represents an unresolved task to date. In this study we investigate the diagnostic accuracy of dobutamine atropine thallium-201 scintigraphy in detection of the presence or absence of coronary artery disease in these patients. Methods and Forty hypertensive patients [55 +/- 7.5 years] with left ventricular hypertrophy documented by echocardiography were included in the study. Dobutamine stress thallium was performed for all patients.Graduated doses of dobutamine were infused Atropine [1mg] was given in patients not achieving 85% of age-predicted maximal heart rate. At peak stress, thallium [3 mci] was injected 4 hours later 1 mci was injected for redistribution images. All patients were subjected to coronary angiography within 2 months from the perfusion study. Systolic blood Pressure increased from [133 +/- 22 mmHg] to [150 +/- 20 mmHg] P=0.0001, heart rate increased from [75 +/- 12 bpm] to [138 +/- 9bpm]p=0.0001. The overall sensitivity, specificity, Positive predictive value negative predictive value and accuracy of thallium.201 SPECT for the diagnosis of coronary artery disease referred to coronary angiography were 84%, 85% 80%, 88% and 84% respectively. The sensitivity and specificity for individual vascular territories were also 76% and 93% for the left anterior descending artery 67% and 83% for the circumflex artery 70% and 97% for the right coronary artery. Dobutamine thalIium-201 Scintigraphy is a safe and feasible method for evaluation of coronary artery disease in hypertensive patients with left ventricular hypertrophy with good sensitivity and specificity for diagnosing and location of coronary artery disease and a diagnostic accuracy comparable to that in patients without hypertension

Effect of percutaneous translumminal coronrary angioplasty on endothelin level

the endothelins are a family of three isopeptides that are extremely potent vasoconstrictors both in vivo and in vitro. The development of sensitive assays has allowed the measurement of the low concentrations of endothelin in plasma. A preliminary study on the release of ET-1 after percutaneous transluminal coronary angioplasty [PTCA] provided neither a control group nor a time course after PCTA. This study was designed to evaluate the time course of ET-1 release in the coronary vascular bed of patients with ischemic heart disease undergoing PTCA. Fifteen patients in sinus rhythm with ischemic heart disease [Canadian Cardiovascular Association class II to III] with mean age [45 +/- 3.5 years] underwent first time coronary angiography, which showed one or more vessel disease [stenosis ranging from 70% to 90%]. ET immuno-reactivity was measured in paried samples of coronary venous blood and peripheral venous blood. The samples were drawn before PTCA and just after the final ballon inflation 10, 30 min PTCA from a peripheral vein. plasma endothelin level in the coronary sinus was significantly increased from 4.2 +/- 1.2 pg / ml to 11.5 +/- 1.9 pg / ml after PTCA [P=0.0001]. these results suggest that the increase of plasma endothelin level in the coronary sinus may be associated with the coronary endothelial injury by PTCA

Usefulness of isometric hand grip exercise in detecting wall motion abnormalities during dobutamine stress echocardiography in patients with acute myocardial infarction

Dobutamine stress echocardiography [DSE] detects coronary artery disease [CAD] by increasing myocardial oxygen demand causing ischemia. The sensitivity of the test for detection of CAD is reduced in patients with sub-maximal stress. It was hypothesized that increasing cardiac work load by adding isometric exercise would improve the detection of ischemia during [DSE]. Thirty patients were studied, with mean age 52 +/- 9 years with history of recent myocardial infarction [3-4 weeks]. Patients underwent [DSE] using incremental dobutamine doses from 5 to 40 ug/ Kg/min to achieve 85% of predicted heart rate. Hand grip was then performed for 3 mm at 50% of maximal voluntary contraction, while dobutamine infusion was maintained at the peak dose. The addition of hand grip during dobutamine stress was associated with a significant increase in systolic blood pressure [138.8 +/- 6.9 vs 150.3 +/- 7.8 mmHg, p=0.001] and left ventricular end systolic circumfrential wall stress [78 +/- 5.3 x 10[3] dynes/cm[2] vs 121 +/- 11.5 x 10[3] dynes/cm[2] p=0.001], heart rate [137 +/- 5 vs 143 +/- 4 bpm, P= 0.001]. Wall motion score index increased from 1.0 at rest to 1.36 +/- 0.15 with dobutamine, and increased further to 1.48 +/- 0.17 with the addition of hand grip [x[2] =55.860, P= 0.001] in vascular distributions rather than the area of infarction during basal conditions ischemia was detected in 19 patients [63%] with dobutamine stress alone and in 25 [84%] after the addition of hand grip. The addition of hand grip during DSE is feasible, and improves the detection of myocardial ischemia, and patients with multi-vessel coronary artery disease [CAD] after acute myocardial infarction