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Habib A Dakik

Publications and source records attributed to Habib A Dakik.

16 recordsLinked to original sources
PubMed2006

An initial strategy of intensive medical therapy is comparable to that of coronary revascularization for suppression of scintigraphic ischemia in high-risk but stable survivors of acute myocardial infarction.

OBJECTIVES: The purpose of this study was to determine the relative benefit of intensive medical therapy compared with coronary revascularization for suppressing scintigraphic ischemia. BACKGROUND: Although medical therapies can reduce myocardial ischemia and improve patient survival after acute myocardial infarction, the relative benefit of medical therapy versus coronary revascularization for reducing ischemia is unknown. METHODS: A prospective randomized trial in 205 stable survivors of acute myocardial infarction was made to define the relative efficacy of an intensive medical therapy strategy versus coronary revascularization for suppressing scintigraphic ischemia as assessed by serial gated adenosine Tc-99m sestamibi myocardial perfusion tomography. All patients at baseline had large total (> or =20%) and ischemic (> or =10%) adenosine-induced left ventricular perfusion defects and an ejection fraction > or =35%. Imaging was performed during 1 to 10 days of hospital admission and repeated in an identical fashion after optimization of therapy. Patients randomized to either strategy had similar baseline demographic and scintigraphic characteristics. RESULTS: Both intensive medical therapy and coronary revascularization induced significant but comparable reductions in total (-16.2 +/- 10% vs. -17.8 +/- 12%; p = NS) and ischemic (-15 +/- 9% vs. -16.2 +/- 9%; p = NS) perfusion defect sizes. Likewise, a similar percentage of patients randomized to medical therapy versus coronary revascularization had suppression of adenosine-induced ischemia (80% vs. 81%; p = NS). CONCLUSIONS: Sequential adenosine sestamibi myocardial perfusion tomography can effectively monitor changes in scintigraphic ischemia after anti-ischemic medical or coronary revascularization therapy. A strategy of intensive medical therapy is comparable to coronary revascularization for suppressing ischemia in stable patients after acute infarction who have preserved LV function.

Adenosine↗
PubMed2006

A multinational study to establish the value of early adenosine technetium-99m sestamibi myocardial perfusion imaging in identifying a low-risk group for early hospital discharge after acute myocardial infarction.

OBJECTIVES: The purpose of this study was to determine whether gated adenosine Tc-99m sestamibi single-photon emission computed tomography (ADSPECT) could accurately define risk and thereby guide therapeutic decision making in stable survivors of acute myocardial infarction (AMI). BACKGROUND: Controversy continues as to the role of noninvasive stress imaging in stratifying risk early after AMI. METHODS: The INSPIRE (Adenosine Sestamibi Post-Infarction Evaluation) trial is a prospective multicenter trial which enrolled 728 clinically stable survivors of AMI who had gated ADSPECT within 10 days of hospital admission and subsequent 1-year follow-up. Event rates were assessed within prospectively defined INSPIRE risk groups based on the adenosine-induced left ventricular perfusion defect size, extent of ischemia, and ejection fraction. RESULTS: Total cardiac events/death and reinfarction significantly increased within each INSPIRE risk group from low (5.4%, 1.8%), to intermediate (14%, 9.2%), to high (18.6%, 11.6%) (p < 0.01). Event rates at 1 year were lowest in patients with the smallest perfusion defects but progressively increased when defect size exceeded 20% (p < 0.0001). The perfusion results significantly improved risk stratification beyond that provided by clinical and ejection fraction variables. The low-risk INSPIRE group, comprising one-third of all enrolled patients, had a shorter hospital stay with lower associated costs compared with the higher-risk groups (p < 0.001). CONCLUSIONS: Gated ADSPECT performed early after AMI can accurately identify a sizeable low-risk group who have a <2% death and reinfarction rate at 1 year. Identifying these low-risk patients for early hospital discharge may improve utilization of health care resources at considerable cost savings.

Adenosine↗
PubMed2006

Utilization of glycoprotein IIb/IIIa inhibitors in non-ST-elevation acute myocardial infarction in a tertiary referral medical center in a developing country.

We analyze the patterns of utilization of glycoprotein (GP) IIb/IIIa inhibitors in patients with non-ST-elevation myocardial infarction (NSTEMI) in a tertiary medical center in a developing country and we compare it to data from the national registry of myocardial infarction 4 (NRMI 4) in the USA. GP IIb/IIIa inhibitors were used in 28% of patients. The significant multivariate predictors of GP IIb/IIIa inhibitors utilization were Age <70 years (p=0.05), TIMI score > or =4 (p=0.002), and the absence of congestive heart failure (p=0.01) or prior infarction (p=0.04). Our results show striking similarity to what has been reported by the NRMI 4 registry, in terms of the overall underutilization of GP IIb/IIIa inhibitors in NSTEMI patients, and particularly in elderly patients and women. These findings underscore the importance of initiating a worldwide campaign to educate physicians about the pivotal role of GP IIb/IIIa inhibitors in the management of patients with NSTEMI.

Aged↗
PubMed2006

Thiazolidinediones associated with recurrent pleural effusions post coronary artery bypass surgery.

We report the case of a patient in which thiazolidinediones (TZDs) were associated with recurrent pleural effusions post coronary artery bypass surgery, in spite of a normal left ventricular function. The potential mechanisms are discussed, particularly in relation to the "vascular leak syndrome". This finding has important implications for the management of diabetic patients who are referred for coronary artery bypass surgery and who are on TZDs for glycemic control.

Coronary Artery Bypass↗
PubMed2005

The management of acute myocardial infarction in developing countries.

Developing countries contribute a major share to the global burden of cardiovascular disease. Acute myocardial infarction (AMI) in particular remains one of the leading causes of death in the developing world as well as in the developed world. While the risk factors, management and outcome of AMI have been extensively studied in the developed world, limited data is available on this subject from developing countries. The current review looks at the prevalence of the classical coronary artery disease risk factors in developing countries and their association with myocardial infarction, as well as the management and outcome of AMI patients in these countries.

Age Distribution↗
PubMed2005

Prevalence of coronary artery calcium among asymptomatic men and women in a developing country: comparison with the USA data.

BACKGROUND: Coronary artery calcium score (CACS) correlates with atherosclerotic burden and predicts cardiac events. Most of the published data have been derived from the USA population. OBJECTIVE: To study the prevalence of coronary calcium in an asymptomatic population from the eastern Mediterranean region and compare it to data obtained from a large population study in the USA. RESULTS: A total of 1154 asymptomatic men and women from Lebanon underwent EBCT screening because of the presence of one or more CAD risk factors. Mean CACS as well as the percentile cut-points increased consistently with increasing age and, except for those above 74 years of age, were higher in men than women in each age stratum. Age, hypercholesterolemia, diabetes and smoking showed significant associations with CACS in men, while only age and hypercholesterolemia were significantly associated with CACS in women. Among men, the 75th and 90th percentile distributions were comparable to what is observed in developed countries such as the USA. CONCLUSION: Findings, from this first study in the region, suggest that despite a higher rate of diabetes and smokers in our study population, the CACS distribution in Lebanon is similar to that observed in the USA.

Adult↗
PubMed2004

Acute myocardial infarction: clinical characteristics, management and outcome in a university medical centre in a developing Middle Eastern country.

BACKGROUND: The management and outcome of acute myocardial infarction (AMI) have not been well studied in developing countries, although demographic data from the World Health Organization indicate that developing countries contribute a major share to the global burden of cardiovascular disease. OBJECTIVES: To analyze the clinical characteristics, management and outcome of patients hospitalized with AMI in a university medical centre in a developing Middle Eastern country. METHODS: The study population comprised all patients hospitalized with AMI at the American University of Beirut between January 1, 1997, and December 30, 1998. The medical records of the patients were reviewed to determine their clinical characteristics, the diagnostic and invasive procedures used during the hospitalization, and any in-hospital complications, including death. RESULTS: The population comprised 184 patients with a mean age of 60+/-13 years. Fifty-two per cent of the infarcts were anterior and 76% developed Q waves. Fifty-one per cent of the patients received thrombolytic therapy. At discharge, 80% of the patients were given acetylsalicylic acid, 35% were given beta-blockers, 34% were given angiotensin-converting enzyme inhibitors and 30% were given statins. Seventy-two per cent of the patients underwent coronary angiography, 23% underwent percutaneous transluminal coronary angioplasty and 13% had coronary artery bypass grafting. The in-hospital mortality was 13%. The predictors of in-hospital mortality were advanced age (over 60 years), diabetes, prior AMI, Killip class greater than I and ejection fraction less that 40%. In contrast, the predictors of coronary angiography were younger age (less than 60 years), absence of diabetes or no history of AMI, Killip class I and ejection fraction greater than 40%. CONCLUSIONS: Coronary angiography after AMI was performed more frequently than expected in a university medical centre in a developing country, and it seemed to be selectively used in the low- risk patients rather than the high-risk ones. Furthermore, the underuse of medical therapy with beta-blockers and statins was evident. These findings should prompt cardiac societies in these countries to initiate educational campaigns focusing on the cost-effectiveness of therapy in AMI to optimize the use of their limited resources.

Cardiovascular Agents↗
PubMed2003

Coronary artery bypass surgery in octogenarians: outcomes in a tertiary referral university hospital in a developing country.

BACKGROUND: The number of people older than 80 years is increasing worldwide and many of these patients are being referred for coronary artery bypass surgery (CABG). Several recent reports from the USA and Europe have shown that CABG can be performed in octogenarians with an acceptable risk. However, data from developing countries regarding this subject is lacking. The objective of this study was to analyze the clinical characteristics and in-hospital events of octogenarian patients undergoing CABG at a tertiary referral university hospital in a developing country. METHODS: The study included 28 consecutive octogenarian patients who underwent CABG at the American University of Beirut, between January 1998 and December 2000. The medical records of these patients were reviewed for demographic information, clinical and catheterization findings, operative characteristics, and in-hospital events (death, myocardial infarction, and stroke). RESULTS: The mean age of the study group was 82 +/- 2 years and 75% were males. Seventy-eight percent of the patients had an acute myocardial infarction or unstable angina prior to CABG. All of the patients were in NYHA class I or II and none of the operations were done on an emergent basis. The mean ejection fraction was 48 +/- 7%. Eighty-six percent of patients had multivessel disease and four patients had aortic valve replacement (AVR) concomitantly with the CABG. The in-hospital mortality was 0%. Three patients (11%) had a post-operative myocardial infarction, and one patient (4%) had a stroke. The mean post-operative stay was 9 +/- 7 days with only three patients (11%) staying for more than 14 days. The multivariate predictors of in-hospital cardiovascular events were concomitant AVR (P=0.01), and an ejection fraction <40% (P=0.03). CONCLUSION: In carefully selected octogenarian patients who are clinically stable in NYHA class I or II, and where the operation is not done on an emergent basis, CABG can be performed with an acceptable risk and a low in-hospital mortality.

Aged↗
PubMed2003

Diffuse coronary artery spasm induced by guidewire insertion.

Coronary artery spasm is reported to occur in 1 5% of percutaneous coronary interventions. However, coronary spasm induced solely by guidewire insertion is very rare. We present a case of diffuse coronary artery spasm induced by guidewire insertion, which responded promptly to intracoronary nitrates. The case illustrates the importance of the recognition of this phenomenon for the selection of the optimal balloon and stent size.

Aged↗
PubMedDate not supplied

Prognostic value of quantitative stress myocardial perfusion imaging in unstable angina patients with negative cardiac enzymes and no new ischemic ECG changes.

BACKGROUND: Limited data are available on the value of quantitative stress myocardial perfusion imaging (MPI) in patients with unstable angina. In this report we sought to study the long-term prognostic value of quantitative stress MPI in patients hospitalized with unstable angina with no new ischemic electrocardiographic changes and negative cardiac enzymes. METHODS AND RESULTS: The study population consisted of 136 patients who were hospitalized at the Methodist Hospital, Houston, Tex, with unstable angina and subsequently underwent MPI before discharge. Cox proportional hazards (regression) analysis was performed to identify clinical and MPI predictors of hard cardiac events (death or nonfatal myocardial infarction). During a mean follow-up of 31 +/- 17 months, 20 patients (15%) sustained either cardiac death (n = 12) or nonfatal myocardial infarction (n = 8). The significant multivariate predictors of cardiac events were the total perfusion defect size ( P = .002), the presence of reversible perfusion defects ( P = .01), and the presence of multiple perfusion defects ( P = .03). The perfusion defect size was significantly larger in patients with events than in those without events (21% +/- 20% vs 12% +/- 14%, P = .002). Kaplan-Meier analysis showed that cardiac events were much more likely to develop in patients with defects involving 15% or more of the left ventricle than in those with defects involving less than 15% of the left ventricle ( P = .003). CONCLUSIONS: In patients hospitalized with unstable angina with no new ischemic electrocardiographic changes and negative cardiac enzymes, quantitative stress MPI provides powerful prognostic information that can be used in the risk stratification of these patients.

Angina, Unstable↗
PubMedDate not supplied

Prognostic value of adenosine Tl-201 myocardial perfusion imaging after acute myocardial infarction: results of a prospective clinical trial.

BACKGROUND: We have previously shown in retrospective studies that adenosine myocardial perfusion imaging (MPI) done after acute myocardial infarction (AMI) can effectively predict the risk of future cardiac events in these patients. The objective of this study was to validate these observations in a prospective clinical trial. METHODS AND RESULTS: One hundred twenty-six stable patients underwent quantitative adenosine MPI at a mean of 4.5 +/- 2.9 days after AMI. On the basis of the MPI results, they were divided into 3 risk groups: low risk (< 20% perfusion defect), intermediate risk (> or = 20% perfusion defect with < 10% ischemia), and high risk (> or = 20% perfusion defect with > 10% ischemia). The patients were followed up for 11 +/- 5 months for the occurrence of cardiac events: death, myocardial infarction, unstable angina, or congestive heart failure. The actual event rates correlated very well with the prespecified risk groups (19% for the low-risk group, 28% for the intermediate-risk group, and 78% for the high-risk group; P < .001). The significant multivariate predictors for events were female gender (relative risk [RR], 2.90; P = .002), left ventricular ejection fraction (RR, 1.34; P = .04), and ischemic defect size (RR, 1.46; P = .001), with a global chi2 value of 26.7. CONCLUSION: This study demonstrates, in a prospectively designed clinical trial, that quantitative adenosine MPI performed soon after AMI can effectively predict the risk of future cardiac events. These findings are currently being validated in an ongoing, large, multicenter, international clinical trial.

Adenosine↗
PubMedDate not supplied

Tl-201 reinjection enhances the detection of myocardial ischemia after acute myocardial infarction.

BACKGROUND: Thallium 201 reinjection has been shown to enhance the detection of myocardial ischemia in patients with chronic coronary artery disease. However, limited data are available regarding its value in patients after acute myocardial infarction. METHODS AND RESULTS: We performed adenosine Tl-201 tomography in 126 patients in stable condition at a mean of 5 +/- 3 days after acute myocardial infarction (MI). After acquisition of redistribution images, patients were reinjected with 1 mCi of Tl-201 and reinjection images were then obtained. The stress, redistribution, and reinjection images were quantified to determine the total perfusion defect size and percent ischemia and scar. The mean age of patients was 54 +/- 10 years. Of the patients, 64% were male, 56% had Q-wave MI, 46% had anterior MI, and 34% received thrombolysis. The percent total defect size was the same on the stress-redistribution and stress-reinjection images (28.3% +/- 19.0%). The reinjection images showed an increase in ischemic defect size (14.7% +/- 13.5% vs 12.8% +/- 12.0%, P =.001) and a decrease in scar defect size (13.6% +/- 13.1% vs 15.5% +/- 13.9%, P =.001) compared with the redistribution images. The enhancement in the detection of myocardial ischemia was seen in both the infarct (P =.001) and noninfarct (P =.01) zones. CONCLUSIONS: Tl-201 reinjection enhances the detection of myocardial ischemia after acute MI compared with stress-redistribution alone.

Female↗
PubMedDate not supplied

Analysis of referral patterns, predictive accuracy, and impact on patient management of myocardial perfusion imaging in a new nuclear cardiology laboratory.

BACKGROUND: Most of the published data on myocardial perfusion imaging (MPI) come from large tertiary-referral medical centers with extensive experience in cardiac imaging as well as a large volume of procedures. Whether the results of MPI remain as reliable in new nuclear cardiology laboratories with smaller volumes of procedures is unknown. The purpose of this study was to analyze the referral patterns, predictive accuracy, and impact of MPI on clinical practice in a newly opened nuclear cardiology laboratory. METHODS AND RESULTS: We performed a prospective study on all patients referred for MPI at our nuclear cardiology laboratory during its first year of operation. Patients were followed up for 3 months after the MPI study to determine whether they underwent coronary angiography. The study population consisted of 334 patients. Their mean age was 56 +/- 10 years, and 80% were men. Of the patients, 30% were asymptomatic, 29% had angina, and only 6% had recent acute myocardial infarction or unstable angina. Fifty-one patients (fifteen percent) were subsequently referred for coronary angiography. The positive and negative predictive values of MPI were 91% and 86%, respectively. The presence of reversible perfusion defects (P =.02) and the presence of multiple perfusion defects (P =.01) on MPI were the most important determinants of subsequent referral to coronary angiography. CONCLUSIONS: MPI stress testing retains its high diagnostic accuracy in a new nuclear cardiology laboratory with a relatively small volume of procedures. Furthermore, MPI findings in this population had a strong impact on the clinical practice of the referring physicians in terms of subsequent referral to coronary angiography.

Cardiology Service, Hospital↗