Farid Jadbabaie

The association of left ventricular ejection fraction, mortality, and cause of death in stable outpatients with heart failure ☆

OBJECTIVES The aim of this study was to assess the prognostic importance of left ventricular ejection fraction (LVEF) in stable outpatients with heart failure (HF). BACKGROUND Although LVEF is an accepted prognostic indicator of prognosis in HF patients, the relationship of LVEF and mortality across the full spectrum of LVEF is incompletely understood. METHODS We examined the association of LVEF and outcomes among 7,788 stable HF patients enrolled in the Digitalis Investigation Group trial. RESULTS During mean follow-up of 37 months, mortality was substantial in all LVEF groups (range, LVEF <or= 15%, 51.7%, LVEF > 55%, 23.5%). Among patients with LVEF <or= 45%, mortality decreased in a near linear fashion across successively higher LVEF groups (LVEF < 15%, 51.7%; LVEF 36% to 45%, 25.6%; p < 0.0001). This association was present after multivariable adjustment, although the magnitude of this associated risk was reduced (LVEF <or= 15%: hazard ratio [HR] 1.77, 95% confidence interval [CI] 1.48 to 2.11; LVEF 16% to 25%: HR 1.44, 95% CI 1.28 to 1.61; LVEF 26% to 35%: HR 1.10, 95% CI 0.98 to 1.28; LVEF 36% to 45%: referent). In contrast, mortality rates were comparable among patients with LVEF > 45% both before (LVEF 46% to 55%: 23.3%; LVEF > 55%: 23.5%; p = 0.25), and after multivariable adjustment (LVEF 46% to 55%: HR 0.92, 95% CI 0.77 to 1.10; LVEF > 55%: HR 0.88, 95% CI 0.71 to 1.09; LVEF 36% to 45%: referent). Patients with lower LVEF were at increased absolute risk of death due to arrhythmia and worsening HF, but these were leading causes of death in all LVEF groups. CONCLUSIONS Among HF patients in sinus rhythm, higher LVEFs were associated with a linear decrease in mortality up to an LVEF of 45%. However, increases above 45% were not associated with further reductions in mortality.

Massive Paradoxical Embolism Caught in the Act

A 33-year-old scientist with recent exertional shortness-of-breath presented with new onset right flank and groin pain. For weeks, he had spent over 16 hours a day at his desk writing a grant. History and physical examination revealed resting tachypnea, sinus tachycardia, tender right flank with (+) Giordano sign, and resting oxygen saturation of 91% on room air. Computed tomography showed recent right renal infarct and ventilation/perfusion scan revealed multiple areas of mismatch. Transthoracic and transesophageal echocardiography revealed a large “snake-like” mass waving in …A 33-year-old scientist with recent exertional shortness-of-breath presented with new onset right flank and groin pain. For weeks, he had spent over 16 hours a day at his desk writing a grant. History and physical examination revealed resting tachypnea, sinus tachycardia, tender right flank with (+) Giordano sign, and resting oxygen saturation of 91% on room air. Computed tomography showed recent right renal infarct and ventilation/perfusion scan revealed multiple areas of mismatch. Transthoracic and transesophageal echocardiography revealed a large “snake-like” mass waving in …

Effects of adenosine and a selective A2A adenosine receptor agonist on hemodynamic and thallium-201 and technetium-99m-sestaMIBI biodistribution and kinetics.

OBJECTIVES The purpose of this study was to compare a selective A(2A) adenosine receptor agonist (regadenoson) with adenosine in clinically relevant canine models with regard to effects on hemodynamics and thallium-201 ((201)Tl) and technetium-99m ((99m)Tc)-sestaMIBI biodistribution and kinetics. BACKGROUND The clinical application of vasodilator stress for perfusion imaging requires consideration of the effects of these vasodilating agents on systemic hemodynamics, coronary flow, and radiotracer uptake and clearance kinetics. METHODS Sequential imaging and arterial blood sampling was performed on control, anesthetized closed-chest canines (n = 7) to evaluate radiotracer biodistribution and kinetics after either a bolus administration of regadenoson (2.5 microg/kg) or 4.5-min infusion of adenosine (280 microg/kg). The effects of regadenoson on coronary flow and myocardial radiotracer uptake were then evaluated in an open-chest canine model of a critical stenosis (n = 7). Results from ex vivo single-photon emission computed tomography were compared with tissue well-counting. RESULTS The use of regadenoson compared favorably with adenosine in regard to the duration and magnitude of the hemodynamic effects and the effect on (201)Tl and (99m)Tc-sestaMIBI biodistribution and kinetics. The arterial blood clearance half-time was significantly faster for (99m)Tc-sestaMIBI (regadenoson: 1.4 +/- 0.03 min; adenosine: 1.5 +/- 0.08 min) than for (201)Tl (regadenoson: 2.5 +/- 0.16 min, p < 0.01; adenosine: 2.7 +/- 0.04 min, p < 0.01) for both vasodilator stressors. The relative microsphere flow deficit (0.34 +/- 0.02%) during regadenoson stress was significantly greater than the relative perfusion defect with (99m)Tc-sestaMIBI (0.69 +/- 0.03%, p < 0.001) or (201)Tl (0.53 +/- 0.02%, p < 0.001), although (201)Tl tracked the flow deficit within the ischemic region better than (99m)Tc-sestaMIBI. The perfusion defect score was larger with (201)Tl (22 +/- 2.8% left ventricular) than with (99m)Tc-sestaMIBI (17 +/- 1.7% left ventricular, p < 0.05) on ex vivo single-photon emission computed tomography images. CONCLUSIONS The bolus administration of regadenoson produced a hyperemic response comparable to a standard infusion of adenosine. The biodistribution and clearance of both (201)Tl and (99m)Tc-sestaMIBI during regadenoson were similar to adenosine vasodilation. Ex vivo perfusion images under the most ideal conditions permitted detection of a critical stenosis, although (201)Tl offered significant advantages over (99m)Tc-sestaMIBI for perfusion imaging during regadenoson vasodilator stress.

Images in cardiovascular medicine. Massive paradoxical embolism: caught in the act.

A 33-year-old scientist with recent exertional shortness-of-breath presented with new onset right flank and groin pain. For weeks, he had spent over 16 hours a day at his desk writing a grant. History and physical examination revealed resting tachypnea, sinus tachycardia, tender right flank with (+) Giordano sign, and resting oxygen saturation of 91% on room air. Computed tomography showed recent right renal infarct and ventilation/perfusion scan revealed multiple areas of mismatch. Transthoracic and transesophageal echocardiography revealed a large “snake-like” mass waving in …A 33-year-old scientist with recent exertional shortness-of-breath presented with new onset right flank and groin pain. For weeks, he had spent over 16 hours a day at his desk writing a grant. History and physical examination revealed resting tachypnea, sinus tachycardia, tender right flank with (+) Giordano sign, and resting oxygen saturation of 91% on room air. Computed tomography showed recent right renal infarct and ventilation/perfusion scan revealed multiple areas of mismatch. Transthoracic and transesophageal echocardiography revealed a large “snake-like” mass waving in …

Unexpected intraoperative diagnosis of pulmonary embolism by transesophageal echocardiography.

Fig 1. The midesophageal ascending aorta short-axis view. The right pulmonary artery in the long axis containing a mass (delineated by arrows) is visible in the near field.

Left Upper Pulmonary Vein Thrombus in a Patient with Atrial Fibrillation and Prior Lobectomy

CASE REPORT A 66-year-old man with chronic obstructive pulmonary disease status-post left upper lobectomy for lung cancer presents with dyspnea. He was diagnosed with atrial fibrillation 2 months previously and managed with metoprolol and coumadin. His examination results are significant for an irregular pulse, elevated jugular venous pressure, and bilateral expiratory wheezing. He is otherwise hemodynamically stable. He is admitted for chronic obstructive pulmonary disease and congestive heart failure and treated with bronchodilators and loop diuretics. Telemetrymonitoring revealed atrial fibrillationwith rapid ventricular response. He continued to have dyspnea and subsequently underwent a transesophageal echocardiogram (TEE) before planned cardioversion, which demonstrated an oval-shaped echodensity in the left upper pulmonary vein consistent with thrombus (Figure 1A-C). No thrombus was seen in the left atrial appendage (Figure 1D). The cardioversion was aborted, and he was maintained on anticoagulation. He continued to have significant dyspnea when seen in outpatient follow-up several weeks later. A repeat TEE documented resolution of the previously seen left upper pulmonary vein thrombus (Figure 1E, F). The patient was prescribed an oral loading dose of amiodarone and converted to sinus rhythm several days later.

Molecular imaging of calcific aortic valve disease

Calcific aortic valve disease (CAVD) can progress to symptomatic aortic stenosis in a subset of patients. The severity of aortic stenosis and the extent of valvular calcification can be evaluated readily by echocardiography, CT, and MRI using well-established imaging protocols. However, these techniques fail to address optimally other important aspects of CAVD, including the propensity for disease progression, risk of complications in asymptomatic patients, and the effect of therapeutic interventions on valvular biology. These gaps may be addressed by molecular imaging targeted at key biological processes such as inflammation, remodeling, and calcification that mediate the development and progression of CAVD. In this review, recent advances in valvular molecular imaging, including 18F-fluorodeoxyglucose (FDG) and 18F-sodium fluoride (NaF) PET, and matrix metalloproteinase-targeted SPECT imaging in the preclinical and clinical settings are presented and discussed.

Diastolic Mitral Regurgitation in Complete Heart Block

A 71-year-old woman presented with generalized weakness and lightheadedness that she had experienced during the prior 24 hours. She reported no chest pain, dyspnea, recent tick bites, rashes, or febrile illnesses. Her blood pressure was 132/47 mmHg, and her pulse rate was 38 beats/min. The remainder of her physical examination revealed nothing of note. Results of routine laboratory tests were normal. Her 12-lead electrocardiogram showed sinus rhythm with 3rd-degree atrioventricular (AV) block, also known as complete heart block (Fig. 1). The patient was admitted to the intensive care unit. Serologic results were negative for Lyme disease. A transthoracic echocardiogram showed moderate diastolic mitral regurgitation (MR) and trace systolic MR in color-f low (Fig. 2A) and continuous-wave spectral Doppler modes (Fig. 2B). The patient underwent implantation of a dual-chamber pacemaker, after which an electrocardiogram showed an atrial-sensed, ventricularpaced rhythm (Fig. 3). A repeat transthoracic echocardiogram showed resolution of her diastolic MR (Fig. 4A) and no signif icant MR during systole (Fig. 4B). The patient’s symptoms resolved, and she was discharged from the hospital.

Massive Paradoxical Embolism

A 33-year-old scientist with recent exertional shortness-of-breath presented with new onset right flank and groin pain. For weeks, he had spent over 16 hours a day at his desk writing a grant. History and physical examination revealed resting tachypnea, sinus tachycardia, tender right flank with (+) Giordano sign, and resting oxygen saturation of 91% on room air. Computed tomography showed recent right renal infarct and ventilation/perfusion scan revealed multiple areas of mismatch. Transthoracic and transesophageal echocardiography revealed a large “snake-like” mass waving in …A 33-year-old scientist with recent exertional shortness-of-breath presented with new onset right flank and groin pain. For weeks, he had spent over 16 hours a day at his desk writing a grant. History and physical examination revealed resting tachypnea, sinus tachycardia, tender right flank with (+) Giordano sign, and resting oxygen saturation of 91% on room air. Computed tomography showed recent right renal infarct and ventilation/perfusion scan revealed multiple areas of mismatch. Transthoracic and transesophageal echocardiography revealed a large “snake-like” mass waving in …