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Shaul Atar

Publications and source records attributed to Shaul Atar.

36 records · Page 2Linked to original sources
PubMed2005

Torsade de pointes in patients on chronic amiodarone treatment: contributing factors and drug interactions.

BACKGROUND: Torsade de pointes is rarely associated with chronic amiodarone treatment, despite the effect of amiodarone on QT interval prolongation. OBJECTIVE: To identify risk factors and associated conditions that may cause TdP in patients on chronic amiodarone treatment. METHODS: We reviewed the data of six consecutive patients on chronic amiodarone treatment who were admitted to the intensive cardiac care unit due to syncope and TdP. RESULTS: The patients' median age was 73.5 years, and five were women. Concomitantly, loratadine was given to two patients and trazodone to one patient. Associated and attributing conditions to the development of TdP were hypokalemia in three patients, drug-induced bradycardia in one and reduced left ventricular function in four. CONCLUSIONS: TdP associated with chronic amiodarone treatment may occur when amiodarone is co-administered with drugs that may potentially prolong QT interval. Additional risk factors for amiodarone-associated TdP include female gender, hypokalemia, reduced left ventricular function and bradycardia.

Aged↗
PubMed2005

'Frozen' posterior mitral leaflet in rheumatic mitral stenosis: incidence and impact on outcome of balloon mitral commissurotomy.

BACKGROUND AND AIM OF THE STUDY: The incidence and clinical significance of immobile and 'frozen' posterior mitral leaflet (FPML) were evaluated in the pathophysiology and immediate outcome of patients with severe pliable mitral stenosis (MS) undergoing percutaneous balloon mitral commissurotomy (PBMC). METHODS: During the past four years, 30 'ideal' patients (mean age 46 +/- 8 years) with Wilkins' score <8, bilateral commissural fusion and absence of commissural calcification underwent peri-procedural echocardiographic analysis. Anterior mitral leaflet (AML) mobility index (MI), chordae tendineae (CT) length, and mitral valve area (MVA) were evaluated. RESULTS: Pre-procedure FPML was noted in 28 patients (93%). All patients achieved MVA > or = 1.5 cm2. Post-procedure MVA in patients with bilateral commissural splitting was 1.9 +/- 0.2 cm2 versus 1.6 +/- 0.1 cm2 in patients with unilateral commissural splitting (p < 0.05). CT lengths directed to the AML and PML were 15 +/- 2 mm and 8 +/- 2 mm, respectively (p < 0.05). MI of the AML before and immediately after PBMC was 0.4 and 0.6, respectively (p < 0.05). None of the patients with FPML showed improved mobility following successful PBMC. CONCLUSION: FPML may be found in most patients with pliable MS. It is mainly a result of short, rigid and fused CT directed to the PML. A 'single-wing door' or a unicuspid valve may be used as a model for rheumatic pliable MS. It is suggested that pre-procedure leaflet morphology and functional assessment should focus on the AML.

Catheterization↗
PubMed2004

Utility and diagnostic accuracy of hand-carried ultrasound for emergency room evaluation of chest pain.

This study examined the utility and accuracy of immediate hand-carried echocardiography in patients presenting to the emergency room with chest pain and a normal or nondiagnostic electrocardiogram. Hand-carried echocardiography was highly concordant (kappa = 0.8) with troponin T tests as well as the discharge diagnosis of acute coronary syndrome, had a 100% sensitivity for the detection of acute coronary syndrome, 93% specificity, and 71% and 100% positive and negative predictive values, respectively.

Adult↗
PubMed2004

Perspectives on the role of ultrasonic devices in thrombolysis.

Reperfusion strategies in acute myocardial infarction and thrombotic vascular occlusion are focused on rapid and complete restoration of antegrade flow in the infarct-related artery in order to maximize myocardial salvage. Due to the limitations of fibrinolytic agents in restoration of vascular flow, ultrasonic clot dissolution alone and concomitantly with fibrinolytic, anti-thrombotic and echocardiographic contrast agents has been intensively studied during the last 2 decades. Ultrasound thrombolysis has been tested in-vitro and in-vivo as well as in patients with acute thrombotic occlusions. We review currently available techniques and methods of ultrasonic thrombolysis and present recent clinical and experimental data. The future role of ultrasonic thrombolysis and the strategy of "power thrombectomy" for treatment of acute coronary syndromes is also discussed.

Catheterization↗
PubMed2004

Massive transient pulmonary air embolism during pacemaker implantation under mild sedation: an unrecognized hazard of snoring.

We present a case of a massive pulmonary air embolism during permanent pacemaker lead implantation under mild sedation in a 73-year-old woman. We used a peel-away sheath that is devoid of a hemostatic valve. The air embolism occurred after deep inspiration associated with loud snoring sounds and resolved after short chest massage and administration of adrenaline. Temporary closure of the intravenous entrance route of the peel-away sheath before inserting the lead may prevent this potentially lethal complication.

Aged↗
PubMed2004

Hand-carried ultrasound improves the bedside cardiovascular examination.

OBJECTIVES: We assessed the clinical utility of hand-carried cardiac ultrasound (HCU) devices to assist physicians in the diagnosis of cardiovascular disease. MATERIALS AND METHODS: We reviewed 42 articles published from 1978 to 2004. RESULTS: The capability and simplicity of the HCU device assist physicians in the diagnosis of cardiovascular disease at the initial patients contact. HCU is particularly useful in the setting of emergency or critical care, community screening, or in remote areas with limited access to health care. CONCLUSION: The inherent limitations of the physical examination as well as the reduced focus and training in physical diagnosis of current and recent medical school graduates has set the stage for the HCU device to modify traditional medical practices by complementing the physical examination with real-time cardiovascular imaging.

Ambulatory Care↗
PubMed2003

Correlation of echo-Doppler aortic valve regurgitation index with angiographic aortic regurgitation severity.

We assessed aortic regurgitation (AR) severity by utilizing multiple echo-Doppler variables in comparison with AR severity by aortic root angiography. Patients were divided into 3 groups: mild, moderate, and severe. An AR index (ARI) was developed, comprising 5 echocardiographic parameters: ratio of color AR jet height to left ventricular outlet flow diameter, AR signal density from continuous-wave Doppler, pressure half-time, left ventricular end-diastolic diameter, and aortic root diameter. There was a strong correlation between AR severity by angiography and the calculated echo-Doppler ARI (r = 0.84, p = 0.0001). As validated by aortic angiography, the ARI is an accurate reflection of AR severity.

Adult↗
PubMed2003

Augmentation of in-stent clot dissolution by low frequency ultrasound combined with aspirin and heparin. An ex-vivo canine shunt study.

INTRODUCTION: Ultrasound can accelerate clot dissolution in vitro and in vivo. We used an ex vivo canine shunt to investigate low frequency ultrasound effects on platelet-rich stent thrombosis. METHODS AND RESULTS: Nitinol stents were expanded to 2 mm in diameter in two perfusion chambers in a parallel shunt and exposed to flowing arterial blood at 2100 s(-1) to generate stent thrombi (n=224 perfusion runs). Dethrombotic effects were assessed during treatment with saline and combined treatment with aspirin and heparin. One stent was exposed to ultrasound (27 kHz, 1.4 W/cm2), while the other was not. Stent thrombi were weighed before and after treatment. There was no significant effect of ultrasound during saline infusion. Treatment with aspirin+heparin alone reduced thrombus weight by 37+/-25% (18.9+/-6.1 to 11.8+/-7.7 mg, p<0.0001). Combined treatment with aspirin+heparin+ultrasound produced a 49+/-23% reduction in thrombus weight (19.0+/-6.3 to 9.6+/-7.8 mg, p<0.0001). The reduction in thrombus weight was significantly greater in aspirin+heparin+ultrasound compared with aspirin+heparin alone (p=0.04). CONCLUSIONS: Transcutaneous ultrasound significantly enhances dethrombotic effect of aspirin plus heparin on preformed stent thrombi. These findings suggest the potential of ultrasound as an adjunct to antithrombotic therapy to improve effectiveness without increasing the risk of bleeding complications during treatment of vascular thrombosis.

Animals↗
PubMed2003

Synergism of aspirin and heparin with a low-frequency non-invasive ultrasound system for augmentation of in-vitro clot lysis.

BACKGROUND: Aspirin, glycoprotein IIb/IIIa inhibitors and heparin are routinely used in acute coronary syndromes. Previously we showed that there is synergism between ultrasound and heparin and tirofiban in augmenting blood clot disruption. However, there is a little data on a possible synergism of low-frequency ultrasound with aspirin for in-vitro clot dissolution, and especially on the combination of aspirin with heparin and/or glycoprotein IIb/IIIa inhibitors. MATERIALS AND METHODS: Human blood clots (n = 320) were incubated for 10 or 20 minutes in saline containing aspirin alone or combined with heparin and/or tirofiban and/or eptifibatide. Clots were randomly treated with low-frequency ultrasound (27.3 kHz) or incubation only. The percent clot weight loss and the incremental effect of ultrasound were calculated. RESULTS: The most significant incremental effect of ultrasound on clot weight reduction was detected with aspirin alone (5.2 +/- 2.3% and 5.2 +/- 2.6% after 10' and 20', p = 0.04 and p = 0.06, respectively) and in combination with heparin (8.8 +/- 2.5% and 11.5 +/- 2.7% after 10' and 20', p = 0.01 and p = 0.0001, respectively). The greatest absolute magnitude of clot weight reduction was observed with ultrasound combined with aspirin and heparin (48.5 +/- 9.5% after 20'). The addition of tirofiban or eptifibatide to aspirin, heparin and ultrasound did not increase clot lysis. However, eptifibatide had significantly better synergism than tirofiban (p = 0.025 and p = 0.015, after 10 and 20 minutes, respectively). CONCLUSIONS: Aspirin alone or in combination with heparin results in significant augmentation of clot lysis and is synergistic with application of low-frequency ultrasound for 10 and 20 minutes only. These results may have important implications for a possible use of low-frequency ultrasound in treatment algorithms of acute coronary syndromes.

Adult↗
PubMed2003

Torsades de pointes and QT prolongation due to a combination of loratadine and amiodarone.

Torsades de pointes (TdP) has not been previously reported with loratadine. A 73-year old woman on chronic treatment with amiodarone for atrial fibrillation received loratadine and presented with syncope and multiple episodes of TdP. We suggest that QT interval should be monitored whenever loratadine is co-administered with drugs that may potentially prolong QT.

Aged↗
PubMed2003

Percutaneous balloon mitral valvuloplasty in patients with severe mitral stenosis and low transmitral diastolic pressure gradient.

An elevated left atrial pressure and high diastolic pressure gradient (DPG) across the mitral valve are the major hemodynamic abnormalities in mitral stenosis (MS). However, a subgroup of patients with severe MS is characterized by low initial DPG. The authors reviewed the clinical, echocardiographic and hemodynamic data as well as procedural results in 180 patients who underwent percutaneous balloon mitral valvuloplasty (PBMV). An initial mean DPG > 10 mmHg was found in 144 patients (80%) (group A) and mean DPG < or = 10 mmHg in 36 patients (20%) (group B). Patients in group A had higher left ventricular ejection fraction (LVEF) than in group B (61 +/- 5% versus 42 +/- 6%, respectively) and higher cardiac index (2.8 +/- 0.4 versus 2.0 +/- 0.3 l/min/m(2) ). In group B 12 patients (33%) had normal LVEF, whereas 24/36 (67%) had reduced LVEF. All the latter had wall motion abnormalities on ventriculography. Unlike group A, intraprocedural echocardiography was essential for monitoring and evaluating immediate results of PBMV in group B. On follow-up of three years, 75% of group A patients and 55% in group B were in functional class I (p < 0.05). PBMV did not significantly improve symptoms in patients in group B who had preprocedure LVEF < or = 35%.

Adult↗
PubMed2003

The subvalvular apparatus in rheumatic mitral stenosis: methods of assessment and therapeutic implications.

The assessment of the structure and function of the subvalvular apparatus (SVA) in patients with rheumatic mitral stenosis (MS) is complex, yet is of major importance prior to therapeutic decision making. Currently available methods of assessment are neither sufficiently accurate nor feasible. We review anatomic and functional aspects of the SVA and define SVA involvement in rheumatic MS. The role of various noninvasive and invasive methods for evaluating the integrity and function of SVA in rheumatic MS, as well as clinical implications and pitfalls in assessment of SVA are also discussed.

Chordae Tendineae↗
PubMed2003

Diagnostic and therapeutic percutaneous cardiac interventions without on-site surgical backup--review of 11 years experience.

BACKGROUND: Current clinical guidelines restrict catheterization laboratory activity without on-site surgical backup. Recent improvements in technical equipment and pharmacologic adjunctive therapy increase the safety margins of diagnostic and therapeutic cardiac catheterization. OBJECTIVE: To analyze the reasons for urgent cardiac surgery and mortality in the different phases of our laboratory's activity in the last 11 years, and examine the impact of the new interventional and therapeutic modalities on the current need for on-site cardiac surgical backup. METHODS: We retrospectively reviewed the mortality and need for urgent cardiac surgery (up to 12 hours post-catheterization) through five phases of our laboratory's activity: a) diagnostic (years 1989-2000), b) valvuloplasties and other non-coronary interventions (1990-2000), c) percutaneous-only balloon angioplasty (1992-1994), d) coronary stenting (1994-2000), and e) use of IIb/IIIa antagonists and thienopiridine drugs (1996-2000). RESULTS: Forty-eight patients (0.45%) required urgent cardiac surgery during phase 1, of whom 40 (83%) had acute coronary syndromes with left main coronary artery stenosis or the equivalent, and 8 (17%) had mechanical complications of acute myocardial infarction. Two patients died (0.02%) during diagnostic procedures. In phase 2, eight patients (2.9%) were referred for urgent cardiac surgery due to either cardiac tamponade or severe mitral regurgitation, and two patients (0.7%) died. The combined need for urgent surgery and mortality was significantly lower in phase 4 plus 5 as compared to phase 3 (3% vs. 0.85%, P = 0.006). CONCLUSION: In the current era using coronary stents and potent antithrombotic drugs, after gaining experience and crossing the learning curve limits, complex cardiac therapeutic interventions can safely be performed without on-site surgical backup.

Angioplasty, Balloon, Coronary↗
PubMed2003

Transient cardiac dysfunction and pulmonary edema in exertional heat stroke.

Exertional heat stroke is a medical emergency that uncommonly results in severe cardiac dysfunction. The military physician diagnosed a 19-year-old military recruit from an elite unit to have exertional heat stroke. Immediate treatment in the field with rapid ice water cooling and vigorous fluid administration resulted in pulmonary edema. Transthoracic echocardiography on admission to the emergency department revealed moderate reduction in left and right ventricular function. After treatment, within a few days, rapid myocardial recovery was noted and persisted after 6 months of follow-up. Possible mechanisms of cardiac dysfunction in exertional heat stroke and treatment strategies are discussed. It is suggested that intravenous fluid administration to patients with suspected exertional heat stroke should preferably be done with appropriate hemodynamic monitoring and after cardiac dysfunction has been ruled out.

Adult↗
PubMed2002

Early appearance of echo-contrast simulating an intracardiac shunt in a patient with liver cirrhosis and intrapulmonary shunting.

Time of appearance of agitated saline contrast in the left atrium is one of the distinguishing features between intracardiac and intrapulmonary shunt. We report a patient with hepatic cirrhosis who had intrapulmonary shunting and had appearance of peripheral venous saline contrast injection in the left heart chambers within 3 cardiac cycles after its appearance in the right heart chambers despite absence of an intracardiac shunt. Thus, time of appearance of saline contrast in the left heart chambers should not be the sole criterion to distinguish intracardiac from intrapulmonary shunt.

Aged↗
PubMed2001

Anginal syndrome due to giant unruptured sinus of Valsalva aneurysm.

This paper presents a rare cause of angina pectoris in a 43-year-old woman. Her evaluation revealed a compressed and proximally occluded right coronary artery by a giant, unruptured, right sinus of Valsalva aneurysm. The aneurysm was surgically resected and the sinus was successfully reconstructed. On follow-up the patient is asymptomatic.

Journal Article↗