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David A Halon

Publications and source records attributed to David A Halon.

At least 19 recordsLinked to original sources
PubMed2006

Pulmonary venous drainage through a highly vascularized left atrial tumor.

We present a patient with symptomatic congestive heart failure due to a left atrial sarcoma infiltrating and apparently occluding the left pulmonary veins. The tumor was highly vascularized and enabled attenuated blood drainage from the left upper and lower pulmonary veins despite intra-operative appearance as completely obliterative, thus avoiding persistent left lung pulmonary edema. The tumor was partially removed and the pathologic findings showed advanced angiogenesis. Malignant tumors may occlude large blood vessels and thus may result in the development of a collateral flow. However, we suggest that highly vascularized tumors (macroscopic totally occlusive) may serve as a sponge and enable attenuated blood flow through the tumor and hence may avoid a complete cut off in blood supply or drainage.

Aged, 80 and over↗
PubMed2006

Uses and limitations of 40 slice multi-detector row spiral computed tomography for diagnosing coronary lesions in unselected patients referred for routine invasive coronary angiography.

BACKGROUND AND AIMS: The value of multi-detector row computed tomography (MDCT) in routine cardiology practice is uncertain. We examined the applicability of MDCT imaging for the diagnosis of obstructive coronary artery disease in a routine clinical setting. METHODS: MDCT scanning (40 slice) was performed in 111 unselected patients referred for invasive coronary angiography (ICA) and findings were compared to an independent quantitative assessment of the ICA on a segmental, vessel and patient basis. RESULTS: Sensitivity and positive predictive value for segmental disease (72.2 and 70.9% respectively, overall) were higher in patients aged > or = 60 years and history of disease > or = 1 year, whereas specificity and negative predictive value were high in all groups. In the patient-based analysis, sensitivity and positive predictive value (84.7 and 87.8%, respectively) were higher, the latter in keeping with the high-patient prevalence of disease, but specificity and negative predictive value (61.5 and 55.2%) were low. CONCLUSIONS: Usefulness of MDCT was significantly influenced by age, duration of coronary artery disease and female gender, and on a patient-based analysis its diagnostic accuracy was not sufficient to replace ICA in a routine clinical setting.

Aged↗
PubMed2006

Brachial reactivity and extent of coronary artery disease in patients with first ST-elevation acute myocardial infarction.

We examined peripheral endothelial function, as measured by brachial artery reactivity, in 49 stable patients with a first episode of acute ST-segment elevation myocardial infarction to examine the relation between extent of coronary disease and peripheral vascular reactivity. Brachial artery reactivity was assessed by ultrasound and flow-mediated dilation (FMD) was calculated as the change in brachial artery diameter after release of suprasystolic blood pressure cuff inflation. FMD was classified as abnormal in (< or =6%) 19 patients (group 1) and as normal in 30 patients (group 2). Average FMDs were 2 +/- 2% in group 1 and 11 +/- 4% in group 2. Patients in group 1 were older (62 +/- 5 vs 54 +/- 11 years, p = 0.02) and more often had a history of hypertension (n = 10, 52%, vs 6, 20%, p = 0.017). Patients with abnormal endothelial function (group 1) had a larger number of coronary obstructive (>or =50%) lesions (3.6 +/- 2.4 vs 2.0 +/- 1.7, p = 0.01) and more extensive coronary disease (1.9 +/- 0.8 vs 1.4 +/- 0.8 vessel disease, p = 0.05). In patients with 3-vessel disease, FMD was lower (4.0 +/- 1.8% vs 8.2 +/- 0.8%, p = 0.04) than in those with lesser coronary involvement. In conclusion, in patients with a first episode of ST-segment elevation myocardial infarction, there was a strong correlation between extent of coronary artery disease and brachial artery reactivity. Patients with localized coronary disease had relatively normal brachial reactivity, whereas those with diffuse coronary disease had more severe abnormal brachial artery reactivity.

Adult↗
PubMed2006

Possible contribution of pericardial tamponade to coronary artery bypass graft occlusion.

We report an association between pericardial tamponade and early post-surgical occlusion of a coronary bypass graft. The presented patient developed pericarditis following myocardial infarction and bypass surgery. He was readmitted with myocardial reinfarction and cardiogenic shock 1 week after surgery. Coronary angiography revealed occlusion of a saphenous-vein graft to the right coronary artery. Concomitantly, pericardial tamponade was diagnosed on the basis of typical hemodynamics and echocardiographic findings. The patient recovered following pericardiocentesis and coronary angioplasty. We suggest a possible link between the 2 pathologies, whereby post-surgical pericarditis led to tamponade which decreased cardiac preload and resulted in systemic hypotension. Decreased coronary perfusion pressure and extrinsic compression by fluid in the pericardial space may have contributed to graft occlusion. Pericarditis and pericardial tamponade may therefore be risk factors for coronary bypass graft occlusion.

Angioplasty, Balloon, Coronary↗
PubMed2006

Prolonged intravenous eptifibatide infusion for prevention of coronary stent thrombosis.

Coronary bare-metal stent thrombosis usually occurs within a week of angioplasty, and may result in myocardial infarction and death. Thrombosis is effectively prevented by antiplatelet therapy with aspirin and clopidogrel. We describe a patient who was unable to ingest oral medication after angioplasty due to gastrointestinal surgery, and was therefore at risk for stent thrombosis. Intravenous eptifibatide was infused for 8 days in order to achieve parenteral platelet inhibition. We suggest a role for long-term intravenous administration of glycoprotein IIb/IIIa inhibitors for prevention of stent thrombosis in patients unable to take oral antiplatelet therapy.

Aged↗
PubMed2006

Reevaluation of routine invasive strategy versus noninvasive testing following uncomplicated ST-elevation myocardial infarction.

BACKGROUND AND AIMS: While current guidelines recommend a selective invasive approach after low-risk ST-elevation myocardial infarction (STEMI) treated by thrombolysis, based on noninvasive identification of patients with residual or inducible myocardial ischemia, in many instances physicians employ a strategy of routine angiography. The present study was undertaken to reexamine the correlation between noninvasive testing and coronary angiography in patients recovering from uncomplicated STEMI with regard to detection and management of residual infarct artery stenosis and to identify patients with multivessel (MVD) or high-risk coronary disease. METHODS: We prospectively performed predischarge exercise testing (ETT) and myocardial perfusion scintigraphy (MPS) prior to routine predischarge coronary angiography in 83/276 consecutive STEMI patients, who after treatment with initial and early thrombolysis, were defined as low risk by ACC/AHA risk classification. RESULTS: ETT was positive for myocardial ischemia in 11/43 (26%) patients with single-vessel disease (SVD) and 11/22 (50%) patients with MVD, but normal or nondiagnostic in the remainder. MPS revealed significant reversible perfusion defects in 13/40 (32%) patients with SVD and 13/22 (59%) patients with MVD. A selective strategy of ETT followed by MPS for nondiagnostic ETT missed residual infarct-related artery stenosis and/or MVD in 31/81 (38%) of the cohort. Among patients who may not otherwise have been referred for angiography, severe (> or =70%) residual stenosis of the infarct-related artery was present in 56% and MVD in 16%. CONCLUSIONS: Early predischarge ETT and/or MPS had limited sensitivity for the detection of coronary disease in low-risk post-STEMI patients. The study supports a simpler strategy of routine coronary angiography in most patients after low-risk STEMI.

Coronary Angiography↗
PubMed2006

Relation between obesity and severity of coronary artery disease in patients undergoing coronary angiography.

We examined the relations among body mass index (BMI), extent of coronary artery disease, and frequency of high-risk coronary anatomy (HRCA) in 928 consecutive patients who underwent coronary angiography during a 6-month period. HRCA was defined as >or=50% stenosis of the left main coronary artery and/or significant 3-vessel coronary artery disease (>or=70% narrowing). BMI was classified into 5 subgroups: low (<21 kg/m(2)), normal (21 to 24 kg/m(2)), overweight (25 to 29 kg/m(2)), obese (30 to 34 kg/m(2)), and severely obese (>or=35 kg/m(2)). Obese patients (BMI >or=30 kg/m(2)) were younger (61.4 +/- 10.7 vs 65.3 +/- 11.4 years, p <0.0001) and had higher prevalences of hyperlipidemia, systemic hypertension, and diabetes mellitus. HRCA was present less often in obese patients (56 of 245, 23%, vs 250 of 683, 37%, p = 0.0002). Multivariate regression analysis showed that advancing age (p <0.0001), male gender (p = 0.007), diabetes mellitus (p = 0.0004), and hyperlipidemia (p = 0.0008) were independent predictors of high-risk anatomy, whereas obesity remained a significant negative independent predictor (p = 0.02). Late (30 to 36 months) mortality was not different between obese (6.9%) and nonobese (8.2%) patients but was significantly higher in patients with HRCA (12.4%) than in those without HRCA (5.6%, p = 0.0003). In conclusion, obese patients who were referred for coronary angiography were younger and had a lower prevalence of HRCA. Obese patients were probably referred for angiography at an earlier stage of their disease, thus explaining the "obesity paradox" in several reports of better short-term outcome in obese patients who undergo cardiac procedures.

Age Factors↗
PubMed2006

Resolution of an intra-coronary filling defect in the proximal left anterior descending coronary artery demonstrated by 64-slice multi-detector computed tomography.

The evolution of acute coronary syndromes (ACS) is not always clearly understood, and our understanding has been limited by the absence of serial information regarding the coronary vasculature in these patients. We describe a young patient with an acute inferior wall myocardial infarction in whom repeat multi-detector computed tomographic scanning (MDCT), supported by invasive studies, revealed a transient filling defect in the proximal left anterior descending coronary artery and nonobstructed circumflex and right coronary arteries. New generation 64-slice MDCT scanning provides a new method for visualizing both the coronary lumen and coronary plaque, and may prove to be a useful tool in improving our understanding of the dynamics of ACS.

Adult↗
PubMed2006

Advantages of multidetector computed tomography angiography in the evaluation of patients with chest pain.

Noninvasive imaging of the coronary arteries using multidetector computed tomography is gaining recognition among clinicians. The rapid evolution of this technology is opening new frontiers in the diagnosis of coronary artery disease. This article reviews the current status and future potential for the application of noninvasive coronary multidetector computed tomography angiography in the assessment of coronary artery stenosis, coronary artery anomalies, mural plaque and coronary stent and bypass graft patency.

Atherosclerosis↗
PubMed2006

Initial experience with a cardiologist-based chest pain unit in an emergency department in Israel.

BACKGROUND: Emergency room triage of patients presenting with chest pain syndromes may be difficult. Under-diagnosis may be dangerous, while over-diagnosis may be costly. OBJECTIVES: To report our initial experience with an emergency room cardiologist-based chest pain unit in Israel. METHODS: During a 5 week pilot study, we examined resource utilization and ER diagnosis in 124 patients with chest pain of uncertain etiology or non-high risk acute coronary syndrome. First assessment was performed by the ER physicians and was followed by a second assessment by the CPU team. Assessment was based on the following parameters: medical history and examination, serial electrocardiography, hematology, biochemistry and biomarkers for ACS, exercise stress testing and/or 64-slice multi-detector cardiac computed tomography angiography. Changes in decision between initial assessment and final CPU assessment with regard to hospitalization and utilization of resources were recorded. RESULTS: All patients had at least two cardiac troponin T measurements, 19 underwent EST, 9 echocardiography and 29 cardiac MDCT. Fourteen patients were referred for early cardiac catheterization (same/next day). A specific working diagnosis was reached in 71/84 patients hospitalized, including unstable angina in 39 (31%) and non-ST elevation myocardial infarction in 12 (10%). Following CPU assessment, 40/124 patients (32%) were discharged, 49 (39%) were admitted to Internal Medicine and 35 (28%) to the Cardiology departments. CPU assessment and extended resources allowed discharge of 30/101 patients (30%) who were initially identified as candidates for hospitalization after ER assessment. Furthermore, 13/23 patients (56%) who were candidates for discharge after initial ER assessment were eventually hospitalized. Use of non-invasive tests was significantly greater in patients discharged from the ER (85% vs. 38% patients hospitalized) (P < 0.0001). The mean ER stay tended to be longer (14.9 +/- 8.6 hours vs. 12.9 +/- 11, P = NS) for patients discharged. At 30 days follow-up, there were no adverse events (myocardial infarction or death) in any of the 40 patients discharged from the ER after CPU assessment. One patient returned to the ER because of chest pain and was discharged after reassessment. CONCLUSIONS: Our initial experience showed that an ER cardiologist-based chest pain unit improved assessment of patients presenting to the ER with chest pain, and enhanced appropriate use of diagnostic tests prior to a decision regarding admission/discharge from the ER.

Adult↗
PubMed2005

Diagnosis of coronary in-stent restenosis with multidetector row spiral computed tomography.

OBJECTIVES: The purpose of this study was to assess the accuracy of a new generation spiral multidetector computed tomography (MDCT) scanner (Brilliance 40, Philips Medical Systems, Cleveland, Ohio) in the diagnosis of coronary in-stent restenosis (ISR). BACKGROUND: Noninvasive imaging of ISR would be clinically useful, but artifacts caused by metallic stent struts have limited the role of early generation MDCT scanners. METHODS: We examined 65 patients (age 63 +/- 12 years, 48 [73.8%] men) with 111 implanted coronary stents who were referred for repeat invasive coronary angiography (ICA). Patients underwent 40-slice MDCT one to three days before scheduled ICA, using intravenous contrast enhancement. Images were reconstructed in multiple formats using retrospective electrocardiographic gating. Stents were viewed in their long and short axes and luminal contrast attenuation graded from MDCT grade 1 (minimal restenosis) to 4 (severe restenosis) by consensus of two observers. RESULTS: In-stent restenosis (>/=60% luminal narrowing by quantitative coronary angiography) was found on ICA in 18 (16.2%) of the stented segments and in 16 (24.6%) patients. The MDCT findings correlated with ICA restenosis, with restenosis in only 1 of 59 (1.6%) MDCT grade 1 segments, but in more than three-quarters (12 of 15, 80%) of MDCT grade 4 segments (sensitivity 72.2%, specificity 92.5%, positive predictive value [PPV] 65.0%, negative predictive value [NPV] 94.5% [five stents not assessable by MDCT considered as restenosis]). Using MDCT grades 3 or 4 combined for restenosis, sensitivity of MDCT was 88.9%, specificity 80.6%, PPV 47.1%, and NPV 97.4%. CONCLUSIONS: In-stent restenosis can be diagnosed with moderate sensitivity using a new generation 40-slice MDCT scanner. The high NPV implies a significant role for MDCT in excluding ISR.

Coronary Restenosis↗
PubMed2005

Benefit of clopidogrel according to timing of percutaneous coronary intervention in patients with acute coronary syndromes: further results from the Clopidogrel in Unstable angina to prevent Recurrent Events (CURE) study.

BACKGROUND: The CURE study demonstrated the benefit of clopidogrel in patients with non-ST elevation (NSTE) acute coronary syndromes (ACSs), including those undergoing percutaneous coronary intervention (PCI). It did not report the relation between clopidogrel and timing of PCI or, more specifically, the role of clopidogrel in patients managed with an early interventional strategy, the current preferred treatment option for patients with NSTE ACSs. In the present study, we examined the relation between clopidogrel therapy, timing of PCI, and cardiovascular (CV) events in patients participating in the CURE study. METHODS: A total of 12562 patients with NSTE ACSs was randomized in double-blind fashion to clopidogrel or placebo (300 mg loading dose, then 75 mg/d) in addition to aspirin for up to 1 year. We analyzed the data of the 2658 CURE patients undergoing PCI and related the incidence of outcome events (CV death/myocardial infarction [MI]) to timing of PCI after randomization: early (< 48 hours, median 1.0 day, n = 370), intermediate (> or = 48 hours to initial hospital discharge, median 6.8 days, n = 1360), and late (after initial hospital discharge, median 47.6 days, n = 928). RESULTS: Clopidogrel showed consistent treatment benefit over the 12-month (mean 9 months) follow-up period irrespective of timing of PCI (relative risk [RR] 0.53 for the early group, RR 0.72 for the intermediate group, RR 0.70 for the late group). After adjustment for propensity to undergo PCI, the greatest treatment benefit of clopidogrel was observed in patients undergoing PCI < 48 hours after randomization (RR 0.45, 95% CI 0.21-0.96, P = .038), although with overlap between groups. The lowest absolute event rate (6.7% CV death/MI) was observed in patients treated with clopidogrel and undergoing PCI within 48 hours. There was no increased risk of major bleeding in the early PCI group. CONCLUSIONS: The benefit of therapy with clopidogrel in addition to aspirin in patients presenting with NSTE ACSs was significant irrespective of the timing of PCI. The combination of clopidogrel and an early (< 48 hours) interventional strategy was associated with low absolute event rates for CV death/nonfatal MI.

Angina, Unstable↗
PubMed2005

Anaemia and heart failure: statement of the problem.

While advances in treatment strategies and pharmacotherapy have produced a dramatic reduction in the mortality of patients with heart failure during the past 15 years, there is still a major challenge to improve patient well being, reduce hospitalizations and reduce mortality further. The prevalence of heart failure is not decreasing, and heart failure is currently a cause for hospitalization in >25% of admissions to internal medicine and cardiology departments. It has recently become apparent that anaemia is present in 20-30% of patients with heart failure, and the severity of anaemia has important implications regarding outcome and prognosis. Anaemia may be due to a number of causes, including iron and vitamin deficiency, insidious blood loss, haemodilution, renal impairment and bone marrow depression with resistance to erythropoietin. In the presence of a damaged heart and often coronary artery disease, anaemia may worsen contractile ability and systolic function, while the necessary volume load and ventricular hypertrophy which accompany anaemia contribute to diastolic dysfunction. Preliminary data show that appropriate treatment of anaemia, based on correction of the underlying cause, with, in most patients, the addition of exogenous erythropoietin and iron therapy, improves ventricular function and clinical status. Treatment of anaemia has opened a new frontier in the management of heart failure. We await the results of ongoing clinical trials for more detailed information regarding appropriate haemoglobin targets, choice of medication and dosing and the degree of improvement that may be expected when the issue of anaemia is properly addressed.

Adult↗
PubMed2004

Evaluation of isoproterenol in patients undergoing resuscitation for out-of-hospital asystolic cardiac arrest (the Israel Resuscitation with Isoproterenol Study Prospective Randomized Clinical Trial).

The Israel Resuscitation with Isoproterenol Study included 79 consecutive patients with witnessed out-of-hospital asystolic cardiac arrest who were resuscitated with epinephrine and atropine and randomized to receive additional isoproterenol or no isoproterenol. The rate of return of spontaneous circulation and survival to hospital admission did not differ in patients receiving standard therapy and those receiving additional isoproterenol.

Adrenergic beta-Agonists↗
PubMed2004

Brachial artery endothelial function in residents and fellows working night shifts.

Brachial artery endothelial function, which is measured as responsiveness to reactive hyperemia (flow-mediated dilation [FMD]) was abnormal in residents and house staff after a 24-hour shift, including night duty. The greatest decrease in FMD was observed in physicians with a longer history of night-shift duty and in those reporting fewer sleeping hours during the shift. The finding that FMD is decreased after night duty raises the issue of the effects of shift duty on cardiovascular function in healthcare personnel, particularly in those undertaking night duty for a prolonged period of time.

Adult↗
PubMed2004

Relation between C-reactive protein, treadmill exercise testing, and inducible myocardial ischemia.

This study examined the relation between high-sensitivity C-reactive protein (CRP), exercise-induced myocardial ischemia, and exercise tolerance in 288 stable patients who underwent maximal treadmill stress testing. CRP was correlated with peak exercise workload, which was consistent with the long-term predictive value of peak workload and CRP for outcome events. There was no correlation of high-sensitivity CRP with stress-induced ischemia, which is consistent with a lack of correlation between CRP and the degree of chronic luminal coronary arterial narrowing.

Aged↗
PubMed2004

Importance of increasing age on the presentation and outcome of acute coronary syndromes in elderly patients.

OBJECTIVES: The study examined differences in presentation and outcome between elderly (> or =70 years) and very elderly (> or =80 years) patients hospitalized for acute coronary syndromes (ACS). BACKGROUND: The elderly constitute an increasingly important sector of patients with ACS but have been underrepresented in many therapeutic trials. METHODS: We compiled a registry of 449 consecutive patients, 251 elderly (70 to 79 years) (septuagenarians, group 1) and 198 very elderly (> or =80 years) (group 2), to examine outcomes in relation to baseline characteristics and treatment. We recorded survival over a period of 24 +/- 4 months and rehospitalization and symptomatic status at 16 +/- 4 months. RESULTS: At index hospitalization, the older cohort (group 2) more often had acute myocardial infarction (35% vs. 9.7%, p < 0.0001), heart failure (33.3% vs. 19.4%, p < 0.001), and renal dysfunction (21.6% vs. 12.3%, p = 0.01). They were less likely to undergo coronary angiography (29.3% vs. 43.8%, p = 0.002), but those selected for angiography more often underwent revascularization so that revascularization rates were similar (22.7% group 2 vs. 24.3% group 1, p = NS). Two-year survival rate was poorer in group 2 (67.4 +/- 3.5% vs. 83.5 +/- 2.5% in group 1, p < 0.0001). Repeat rehospitalization was similar (53.0% vs. 48.2%, respectively, p = 0.31), but improvement in well-being of survivors was greater (60.0% vs. 46.3%, p = 0.01). CONCLUSIONS: The study demonstrated important differences between elderly (70 to 79 years) and very elderly (> or =80 years) patients hospitalized with ACS. The older cohort was sicker on admission and had poorer outcome, but a subgroup selected for angiography and possible intervention had two-year outcomes similar to the younger cohort.

Age Factors↗