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Biomedical subjects

Itzhak Kronzon

Publications and source records attributed to Itzhak Kronzon.

At least 37 records · Page 2Linked to original sources
PubMed2004

Mortality in patients with paravalvular abscess diagnosed by transesophageal echocardiography.

BACKGROUND: Paravalvular abscess is a complication of endocarditis that may lead to persistent infection, conduction abnormalities, fistula formation, worsening congestive heart failure, and death. METHODS: Between 1991 and 2001, paravalvular abscess was identified on transesophageal echocardiography in 24 patients who subsequently underwent surgical treatment. Echocardiographic findings were reviewed for location of abscess, presence of a valvular prosthesis, valvular function, and presence of vegetations. Information gathered included the time interval between transesophageal echocardiography diagnosis and operation, inhospital mortality, and microbiologic data. RESULTS: Of 24 patients, 9 died, for a mortality of 38%. Of the patients who died, the average survival after operation was 43 days, with a range of 1 to 238 days. Of the 14 patients with significant valvular or paravalvular regurgitation, 8 died (57%). However, of the 10 patients with mild or no regurgitation, only 1 died (10%). This difference was statistically significant (P =.02). CONCLUSION: Patients without preserved valve function (those with moderate or severe regurgitation) have a significantly worse outcome (57% mortality) than do those with normal valvular function (10% mortality).

Abscess↗
PubMed2004

Comparison of image quality between a narrow caliber transesophageal echocardiographic probe and the standard size probe during intraoperative evaluation.

BACKGROUND: Transesophageal echocardiography (TEE) has become an integral part of the evaluation and monitoring of patients during cardiac operation. Until recently, the smallest TEE probe with multiplane imaging measured 13 mm in diameter. This size is now standard for adult TEE probes. Recently, a new TEE probe has become available (MiniMulti TEE probe, Philips Medical Systems, Andover, Mass), which has a diameter of 8 mm. Although using a smaller probe is attractive, the quality of images it generates when used in adults has not yet been examined. OBJECTIVE: The purpose of this study was to compare TEE studies done with both probes. METHODS: After informed consent was obtained, full intraoperative TEE studies were performed in 20 patients with a small pediatric probe. The study was then repeated using a standard adult probe. The studies were read in random order by two experienced echocardiographers blinded to probe used. For each study, 18 anatomic cardiac structures and 5 Doppler patterns were subjectively graded as excellent (1), good (2), fair (3), or poor (4) in quality. The average score for each structure or Doppler profile was computed for each probe. RESULTS: The average score for all findings was lower (better) for the adult TEE probe (1.4 +/- 0.4 vs 1.7 +/- 0.4; P =.003). When each finding was compared separately, several cardiac structures (left ventricle [LV], pericardium, right ventricle [RV], interatrial septum, left atrium, left atrial appendage, mitral valve, aortic valve) had better scores with the adult probe, and the differences for the LV and RV were larger than those for the other findings (LV scores differed by 0.7, P =.0004; RV scores differed by 0.5, P =.01). There was no significant difference between probes when evaluating venous structures (coronary sinus, superior vena cava, pulmonary vein), the thoracic aorta, or the right atrium or tricuspid valve. In addition, Doppler patterns were not significantly different with the two probes. There were two findings that were missed with the small probe and seen with the adult probe (one aortic plaque and one left atrial appendage thrombus). CONCLUSIONS: In the adult, the larger probe provides better images, particularly of the RV and LV. In addition, important findings may be missed with the smaller probe. However, if the adult probe cannot be passed, the pediatric probe is a reasonable alternative.

Aged↗
PubMed2004

Propensity case-matched analysis of off-pump coronary artery bypass grafting in patients with atheromatous aortic disease.

OBJECTIVE: Atheromatous aortic disease is a risk factor for excessive mortality and stroke in patients undergoing coronary artery bypass grafting. Outcomes of off-pump coronary artery bypass grafting and coronary artery bypass grafting with cardiopulmonary bypass in patients with severe atheromatous aortic disease were compared by propensity case-match methods. METHODS: Routine intraoperative transesophageal echocardiography identified 985 patients undergoing isolated coronary artery bypass grafting with severe atheromatous disease in the aortic arch or ascending aorta. Off-pump coronary artery bypass grafting was performed in 281 patients (28.5%). Propensity matched-pairs analysis was used to match patients undergoing off-pump coronary artery bypass grafting (n = 245) with patients undergoing coronary artery bypass grafting with cardiopulmonary bypass. RESULTS: Univariate analysis revealed decreased hospital mortality (16/245, 6.5% vs 28/245, 11.4%; P =.058) and stroke prevalence (4/245, 1.6% vs 14/245, 5.7%; P =.03) in off-pump coronary artery bypass grafting compared with coronary artery bypass grafting with cardiopulmonary bypass. Freedom from any postoperative complication was higher in off-pump coronary artery bypass grafting compared with coronary artery bypass grafting with cardiopulmonary bypass (226/245, 92.2% vs 196/245, 80.0%; P <.001). Multivariable analysis of preoperative risk factors showed that increased hospital mortality was associated with coronary artery bypass grafting with cardiopulmonary bypass (odds ratio = 2.7; P =.01), fewer grafts (P =.05), acute myocardial infarction (odds ratio = 11.5; P <.001), chronic obstructive pulmonary disease (odds ratio = 2.4; P =.03), previous cardiac surgery (odds ratio = 10.2, P =.05), and peripheral vascular disease (odds ratio = 2.1; P =.05). Cardiopulmonary bypass was the only independent risk factor for stroke (odds ratio = 3.6, P =.03). At 36 months' follow-up, comparable survival was observed in the off-pump coronary artery bypass grafting and coronary artery bypass grafting with cardiopulmonary bypass groups (74% vs 72%). Multivariable analysis revealed that renal disease (P <.001), advanced age (P <.001), previous myocardial infarction (P =.03), and lower number of grafts (P =.02) were independent risks for late mortality. CONCLUSIONS: Patients with severe atherosclerotic aortic disease who undergo off-pump coronary artery bypass grafting have a significantly lower prevalence of hospital mortality, perioperative stroke, and overall complications than matched patients who underwent coronary artery bypass grafting with cardiopulmonary bypass. Routine intraoperative transesophageal echocardiography identifies severe atheromatous aortic disease and directs the choice of surgical technique.

Aged↗
PubMed2004

Isolated subclavian artery aneurysm: evaluation by transesophageal echocardiography.

A 50-year-old man was evaluated following a motor vehicle accident. Chest X-ray showed a widened mediastinum. Transesophageal echocardiography was helpful in identifying the left subclavian artery and in demonstrating an isolated subclavian artery aneurysm. The TEE findings correlated well with the results of chest CT. Using TEE for the identification of the aortic branches in patients with chest trauma may be critical.

Accidents, Traffic↗
PubMed2004

Intraoperative echocardiography in minimally invasive cardiac surgery and novel cardiovascular surgical techniques.

Minimally invasive cardiovascular surgery has been developed in an effort to decrease hospital length of stay and cost by decreasing pulmonary and neurologic complications, pain, chest trauma, and infection. The smaller incisions provide less direct cardiac visualization and exposure, which makes transesophageal echocardiography an essential and integral part of these innovative procedures. Transesophageal echocardiography does not obstruct the surgical field and can perform a full evaluation of the heart. This includes assessment of the aorta and great vessels, valve function, ventricular wall motion, placement of catheters and cannulae, hemodynamic monitoring, and immediate evaluation of surgical results and complications.

Coronary Artery Bypass↗
PubMed2003

Off-pump coronary artery bypass grafting reduces mortality and stroke in patients with atheromatous aortas: a case control study.

BACKGROUND: Patients with severe atheromatous aortic disease (AAD) who undergo coronary artery bypass (CABG) have an increased risk of death and stroke. We hypothesized that in these high risk patients, off-pump coronary artery bypass (OPCAB) technique is associated with lower morbidity and mortality. METHODS AND RESULTS: Between June 1993 and January 2002, 5737 patients undergoing CABG had routine intra-operative TEE with 913 (15.9%) found to have severe AAD in the aortic arch or ascending aorta. Of these, 211 patients who underwent OPCAB were matched with 211 on-pump CABG patients by age, ejection fraction, history of stroke, cerebrovascular disease, diabetes, renal disease, nonelective operation, and previous cardiac surgery. Hospital mortality was 11.4% (24/211) for on-pump CABG and 3.8% (8/211) for OPCAB (P=0.003). Multivariate analysis revealed that increased mortality was associated with on-pump CABG (P=0.001), acute MI (P=0.03), number of grafts (P=0.01), age (P=0.01), history of stroke or cerebrovascular disease (P=0.04), CHF (P=0.02), and peripheral vascular disease (P=0.03). Multivariate analysis showed that OPCAB technique was associated with decreased stroke (P=0.05). Freedom from any complication was 78.7% for on-pump CABG and 91.9% for OPCAB (P<0.001). At 36 month follow-up multivariate analysis revealed that increased mortality was associated with age (P=0.001), previous MI (P=0.03), and renal disease (P=0.04), whereas increased survival was associated with increased number of grafts (P=0.001) and OPCAB (P=0.01). CONCLUSIONS: OPCAB surgery in patients with severe AAD is associated with lower risk of death, stroke and complications and improved mid-term survival. Routine intra-operative TEE allows identification of these patients and directs choice of appropriate surgical technique.

Aged↗
PubMed2003

Iatrogenic Femoral Artery Pseudoaneurysm.

A small (< 6 cm(3) in volume or 1.8 cm in diameter), uncomplicated iatrogenic femoral artery pseudoaneurysm in a reliable patient not requiring anticoagulation can be safely observed with weekly physical examinations and ultrasound evaluations until full thrombosis is documented. The patient should be informed that any symptoms or complications should be reported to a physician immediately. A pseudoaneurysm associated with limb ischemia, severe infection, neurologic deficit, skin necrosis, rapid expansion, or hemorrhage should be treated surgically. Also, surgery is recommended if less invasive treatment strategies have failed, or if a planned surgical procedure involving the groin is anticipated. Given its high success rate, low complication rate, and cost-effectiveness, ultrasound-guided thrombin injection should be considered as first-line treatment for uncomplicated iatrogenic femoral pseudoaneurysm. Ultrasound-guided compression repair is an effective alternative to thrombin injection, especially in institutions that have little or no experience with thrombin injection. Alternative treatment strategies, such as percutaneous endovascular stenting and perfusion ballooning, are generally not recommended as first-line treatment options, because they have not been studied as extensively as ultrasound-guided compression repair or thrombin injection. If no other options are available, however, these alternative approaches may be appropriate in certain clinical situations.

Journal Article↗
PubMed2003

Unusual right ventricular flow pattern in a patient with inferior wall myocardial infarction.

We describe a case of an unusual right ventricular flow pattern in a patient with inferior wall myocardial infarction associated with massive right ventricular infarction. Echocardiography was significant for nearly continuous antegrade flow through both the tricuspid and pulmonic valves demonstrated by color and pulsed wave Doppler. The tricuspid and pulmonic valves remained open throughout the cardiac cycle. These findings signify the nearly complete loss of right ventricular pumping function, and indicate that the right heart was serving as a passive conduit with a flow pattern similar to a vein.

Echocardiography, Doppler, Color↗
PubMed2003

Routine intraoperative transesophageal echocardiography identifies patients with atheromatous aortas: impact on "off-pump" coronary artery bypass and perioperative stroke.

BACKGROUND: Patients with severe atheromatous aortic disease (AAD) undergoing coronary artery bypass grafting (CABG) have increased operative risks. The "off-pump" CABG (OPCAB) technique was evaluated in patients given the diagnosis of severe AAD by routine transesophageal echocardiography. METHODS: A total of 5737 patients underwent CABG, with 913 having transesophageal echocardiography findings of severe AAD. Of the patients with severe AAD, 678 (74.3%) had conventional CABG and 235 (25.7%) had OPCAB. RESULTS: Hospital mortality was 8.7% for conventional CABG and 5.1% for OPCAB (P =.08). Multivariate analysis revealed that increased mortality was significantly associated with acute myocardial infarction, conventional CABG, age, renal disease, history of stroke, and ejection fraction < 30%. Neurologic complications occurred in 6.3% of patients undergoing CABG and in 2.1% undergoing OPCAB (P =.01). Freedom from any complication was significantly greater with OPCAB. CONCLUSION: Routine intraoperative transesophageal echocardiography identifies patients with severe AAD. In these patients, OPCAB technique is associated with a lower risk of death, stroke, and all complications.

Aged↗
PubMed2003

The enigma of occult mitral regurgitation in a patient with cardiogenic shock.

In patients with mitral regurgitation (MR), there is a high pressure gradient between the left ventricle (LV) and left atrium that Doppler echocardiography can easily detect. We present a case where transthoracic echocardiography (TTE) failed to provide an accurate evaluation of a patient who presented in cardiogenic shock. A transesophageal echocardiogram diagnosed MR because of a flail leaflet caused by a ruptured papillary muscle in the setting of normal ventricular function.

Aortic Aneurysm, Abdominal↗
PubMed2003

The a-dip of aortic regurgitation.

Echocardiography has become the diagnostic technique of choice for delineating the intracardiac hemodynamics in a host of pathophysiologic states. Pressures and flows can be estimated or measured with enough accuracy to allow for clinical decision-making. We present a case with an unusual Doppler echocardiographic finding and discuss its derivation.

Aged↗
PubMed2003

Hand carried echocardiography in the critical care setting.

Miniaturized echocardiography units known as hand carried ultrasound (HCU) now exist with features similar to those used for standard echocardiography. The small size and low cost of these units may lead to increased availability of echocardiography to be performed by all physicians taking care of critically ill patients. Use of HCU by critical care physicians may allow for improved bedside diagnosis with improved accuracy over physical examination. Studies comparing HCU with standard echocardiography in the critical care setting have reported that HCU is limited by decreased image quality and that it may miss important diagnoses even when used by experienced sonographers and echocardiographers. Despite its limitations, however, HCU can often answer important clinical questions in the critically ill. This review explores the current literature on the use of HCU in the critical care setting, discusses the limitations of HCU, and examines the costs of implementing this new technology.

Costs and Cost Analysis↗
PubMed2003

Avoiding the left internal mammary artery during anterior pericardiocentesis.

In patients with pericardial effusions who require anterior pericardiocentesis, it is important to avoid trauma to the left internal mammary artery. Such trauma could result in severe bleeding or tamponade. This article describes how the left internal mammary artery may be identified by duplex ultrasound, and therefore avoided. It is also important to ensure that the needle stick is just lateral to the artery, to avoid hitting the left lung.

Aged↗
PubMed2003

Bilateral pulmonary artery compression and obstruction by tumor: diagnosis by unusual Doppler flow patterns.

Pulmonary artery obstruction may be caused by tumor within or external to the arteries. Presented here is a patient with life-threatening compromise in pulmonary flow that was caused by a pulmonary neoplasm. The Doppler echocardiogram showed subtotal narrowing of the right pulmonary artery and total occlusion of the left pulmonary artery. In addition, the beneficial effects of chemotherapy were documented by Doppler.

Constriction, Pathologic↗
PubMed2003

Sensitivity of transthoracic versus transesophageal echocardiography for the detection of native valve vegetations in the modern era.

BACKGROUND: Thirteen years ago, transthoracic echocardiography (TTE) was found to be less sensitive than transesophageal echocardiography (TEE) for native valve vegetations. Since then, harmonic imaging and other advances have improved TTE. How this affects the sensitivity of TTE is unknown. METHODS: Fifty patients with echocardiography-diagnosed endocarditis had TTE and TEE examinations on high-end machines. These were matched for date of study with 50 patients who had TTE and TEE examinations that were negative for vegetations. RESULTS: A total of 51 vegetations were seen on TEE. The sensitivity of TTE for vegetations was only 55% (aortic 50% [12/24]; mitral 62% [16/26]; tricuspid 0% [0/1]). Anatomic valvular abnormalities did not alter the sensitivity of TTE (P =.42 for mitral; P =.97 for aortic valves). However, larger vegetations were more likely to be found by TTE. CONCLUSION: Despite advances in imaging during 12 years, TTE is still insensitive compared with TEE for the detection of native valve vegetations, and fails to demonstrate nearly half of them.

Aged↗