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Robert M Applebaum

Publications and source records attributed to Robert M Applebaum.

10 recordsLinked to original sources

Impact of moderate functional mitral insufficiency in patients undergoing surgical revascularization.

BACKGROUND: Mild and moderate functional ischemic mitral insufficiency present at the time of surgical revascularization present clinical uncertainty. It is unclear whether the relatively poor outcomes in this cohort are dependent on valvular function or related to left ventricular dysfunction. The purpose of this study was to examine the early and late outcomes in patients with less-than-severe functional ischemic mitral insufficiency at the time of isolated coronary artery bypass grafting (CABG). METHODS AND RESULTS: From 1996 through 2004, 2242 consecutive patients undergoing isolated CABG were identified as having none to moderate mitral regurgitation (MR) and no valve leaflet pathology. All of the patients at this single institution routinely had an intraoperative transesophageal echocardiography, prospectively quantified MR, and ejection fraction (EF). The New York State Cardiac Surgery Reporting System infrastructure was used to prospectively collect in-hospital patient variables and outcomes. Social Security Death Benefit Index was used to determine long-term survival. Odds ratio and significance (P value) are presented for each determined risk factor. There were 841 patients (37.5%) with no MR, 1137 (50.7%) with mild MR, and 264 (11.8%) with moderate MR. The patients with moderate MR were more likely to be older, female, and have more renal disease, previous MI, congestive heart failure, previous cardiac surgery, and lower EFs. Hospital mortality was independently and significantly associated with renal disease, decreasing EF, increasing age, previous cardiac operation, and cerebral vascular disease. Multivariable analysis revealed decreased survival with increasing age, previous operation, congestive heart failure, diabetes, nonelective operation, decreasing EF, and the presence of moderate MR (expbeta = 1.49; P=0.007) and mild MR (expbeta = 1.34; P=0.033). CONCLUSIONS: Independent of ventricular function, mild and moderate functional mitral insufficiency are associated with significantly decreased survival in patients undergoing CABG. Whether correction of moderate functional MR at the time of CABG improves outcome still needs to be determined.

Aged↗

Semirigid partial annuloplasty band allows dynamic mitral annular motion and minimizes valvular gradients: an echocardiographic study.

BACKGROUND: Traditional mitral annuloplasty devices include both rigid rings, which restrict annular motion, and soft rings and bands, which can locally deform. Conflicting data exist regarding their impact on annular dynamics. We studied mitral annuloplasty with a semirigid partial band and with a nearly complete rigid ring. METHODS: Intraoperative three-dimensional transesophageal echocardiograms (n = 14) and predischarge transthoracic echocardiograms were retrospectively analyzed in patients undergoing mitral valve repair for degenerative disease with either a rigid ring (n = 77) or a semirigid partial band (n = 38). Each transesophageal echocardiogram was analyzed with TomTec three-dimensional software to produce cardiac cycle frame planimetry and to measure device geometry. Actual device sizes provided reference dimensions. Blinded analysis of Doppler data from transthoracic echocardiograms was performed. RESULTS: Validation of the quantitative transesophageal echocardiogram methodology revealed a 1.3% +/- 0.3% (mean +/- standard error of the mean) underestimation of actual linear dimension. With the semirigid partial band, systolic valve orifice area and intertrigonal distance decreased from 6.14 +/- 0.37 to 5.55 +/- 0.24 cm(2) (-9.6%; p = 0.01) and from 2.69 +/- 0.08 to 2.55 +/- 0.13 cm (-5.2%; p = 0.03), respectively. Systolic anterior-posterior distance decreased from 2.1 +/- 0.10 to 1.95 +/- 0.06 cm (-7.1%; p = 0.01) compared with diastole. In contrast, rigid ring orifice area was unchanged (4.12 +/- 0.15 to 4.10 +/- 0.16 cm(2); -0.5%; p = 0.48) during the cardiac cycle. Transthoracic echocardiography revealed significantly lower mitral inflow gradients with semirigid partial band (mean gradients compared with rigid ring, 4.0 +/- 0.3 versus 5.0 +/- 0.3 mm Hg; p = 0.02; peak gradients, 8.9 +/- 0.5 versus 11.1 +/- 0.5 mm Hg; p = 0.01). CONCLUSIONS: Three-dimensional transesophageal echocardiographic measurements of annular dynamics are valid and reliable when discrete annuloplasty devices are present. In contrast to the rigid ring, the semirigid partial band permits more physiologic geometric changes and is associated with lower postoperative mitral valve gradients.

Echocardiography, Doppler↗

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↗

Anterior leaflet resection of the mitral valve.

Triangular resection is a reconstructive option for treatment of anterior leaflet mitral disease with segmental prolapse. In our experience, it is a safe and reproducible technique, associated with low rates of recurrent MR or need for reoperation, as well as decreased likelihood for systolic anterior motion after mitral repair. We review our experience with this technique over a 25-year experience with mitral valve reconstruction.

Adolescent↗

Aortic valve replacement in patients with impaired ventricular function.

BACKGROUND: Patients with reduced ventricular function undergoing aortic valve replacement have increased operative risks, but the impact of valvular pathophysiology and other risk factors has not been clearly defined. METHODS: From June 1992 through June 2002, 1,402 consecutive patients underwent isolated aortic valve surgery with or without coronary artery bypass grafting; of these patients, 416 had an ejection fraction less than 40% and are the subject of this report. These patients (mean age, 68.6) had severe stenosis (62.5%), severe regurgitation (30.3%), or mixed disease (7.2%). Aortic valve replacement plus coronary artery bypass grafting was performed in 48.4% of patients, and 27% had previous cardiac surgery. Follow-up included echocardiography and survival analysis. RESULTS: Hospital mortality was 10.1% (42 of 416), with no difference between aortic stenosis (9.6%) and regurgitation (11.1%). Multivariate analysis revealed that age (p = 0.002) and renal disease (odds ratio = 4.2; 95% confidence interval, 1.9 to 9.3; p = 0.001) were independently associated predictors of mortality. Valvular pathophysiology had no impact on mortality. Peripheral vascular disease, multivessel coronary disease, and renal disease were associated risks for any postoperative complication. Peripheral vascular disease (odds ratio = 12.3, p = 0.02), history of cerebrovascular disease (odds ratio = 4.8, p = 0.038), and diabetes (odds ratio = 2.7, p = 0.04) were associated risks for stroke. The ejection fraction was more than 40% in 52% of the patients who had postoperative echocardiography (mean follow-up, 6 months). Actuarial survival revealed no difference between pathophysiologic groups. CONCLUSIONS: Aortic valve surgery in patients with impaired ventricular function carries an acceptable operative risk that can be stratified by age and comorbidities. The type of valvular pathophysiology does not significantly affect mortality.

Aged↗

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↗

Substernal epicardial echocardiography: review of a new technique.

BACKGROUND: Patients after cardiac operation pose a challenge to the treating physician-these patients may become critically ill and are among the most difficult to image using transthoracic echocardiography. Several factors contribute to this, including difficulties in positioning the patient, inability of the patient to cooperate with instructions, surgical dressings, and hyperinflated lungs. Transesophageal echocardiography may be performed when transthoracic echocardiography is not diagnostic; however, transesophageal echocardiography is semi-invasive and does not lend itself to prolonged or repeated monitoring. METHODS: Recently, a new approach to echocardiography for use in the patient after operation has been introduced with the modification of the standard mediastinal drainage tube to allow for substernal epicardial echocardiography (SEE). The SEE tube has 2 lumens. The first allows for routine mediastinal drainage and the second has a blind end that permits the insertion of a standard transesophageal echocardiographic probe for high-resolution imaging as often as is desired over the period during which the mediastinal tube is in place. CONCLUSION: This article reviews the technique of SEE including a description of the method of performance of SEE (with representative images), a review of the published literature on this new modality, examples of clinical use, and a discussion of the advantages, indications, and limitations of SEE with an eye toward future directions for research.

Aged↗

Effect of treatment on the incidence of stroke and other emboli in 519 patients with severe thoracic aortic plaque.

Severe aortic plaques seen on transesophageal echocardiography (TEE) are a high-risk cause of stroke and peripheral embolization. Evidence to guide therapy is lacking. Retrospective information was obtained regarding the occurrence of embolic events (stroke, transient ischemic attacks, or peripheral emboli) in 519 patients with severe thoracic aortic plaque seen on TEE since 1988. Treatment with statins, warfarin, or antiplatelet medications was noted. Treatment was not randomized. In a matched-paired analysis, each patient taking each class of therapy was matched for age, gender, previous embolic event, hypertension, diabetes, congestive failure, and atrial fibrillation to someone not taking that medication. Multivariate analysis was also performed. An embolic event occurred in 111 patients (21%). Multivariate analysis showed that statin use was independently protective against recurrent events (p = 0.0001). Matched analysis also showed a protective effect of statins (p = 0.0004; absolute risk reduction 17%, relative risk reduction 59%, number needed to treat [n = 6]). No protective effect was found for warfarin or antiplatelet drugs. The odds ratio for embolic events was 0.3 (95% confidence interval [CI] 0.2 to 0.6) for statin therapy, 0.7 (95% CI 0.4 to 1.2) for warfarin, and 1.4 (95% CI 0.8 to 2.4) for antiplatelet agents. Thus, there is a protective effect of statin therapy, and no significant benefit of warfarin or antiplatelet drugs on the incidence of stroke and other embolic events in patients with severe thoracic aortic plaque on TEE.

Aged↗

The risk of the development of aortic stenosis in patients with "benign" aortic valve thickening.

BACKGROUND: Aortic valve thickening (AVT) without aortic stenosis (AS) is common and was often considered benign. However, it has recently been found to be associated with increased morbidity and mortality. It is unknown whether patients with AVT are at risk for the development of AS. METHODS: Our echocardiography database from 1987 to 1993 was searched for cases of AVT with at least 1 year of echocardiographic follow-up. The risk of the development of AS was compared in patients with and without AVT. RESULTS: There were 2131 patients with AVT and at least 1 year of echocardiographic follow-up. Aortic stenosis developed in 338 patients (15.9%) (mild, 10.5%; moderate, 2.9%; and severe, 2.5%). Multivariate analysis, including age, left ventricular hypertrophy, and mitral annular calcification, revealed that only mitral annular calcification was independently and significantly associated with progression to AS. CONCLUSIONS: Aortic valve thickening without stenosis is common, and it may progress to significant AS. It is possible that this development of AS may be responsible for some of the increased morbidity and mortality in patients with AVT.

Aged↗