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Biomedical subjects

J K Oh

Publications and source records attributed to J K Oh.

At least 55 records · Page 3Linked to original sources
PubMed1998

Hypertrophic cardiomyopathy with obstruction: important diagnostic clue provided by the direction of the mitral regurgitation jet.

We present an unusual case of hypertrophic cardiomyopathy complicated by mitral regurgitation resulting from chordal rupture with flail posterior mitral leaflet. The diagnosis was suggested by the presence of an anteriorly directed mitral regurgitation jet on transthoracic color flow imaging, in addition to the typical posterolateral-lateral jet caused by systolic anterior mitral motion. The flail posterior leaflet was confirmed by transesophageal echocardiography, and the patient underwent mitral valve repair in addition to myectomy. This combination of hypertrophic cardiomyopathy and flail mitral leaflet usually requires surgical intervention, and prompt diagnosis is important. The presence of an anteriorly directed mitral regurgitant jet should always raise suspicion of posterior mitral leaflet abnormality.

Cardiomyopathy, Hypertrophic↗
PubMed1998

Retained left atrial catheter: an unusual cardiac source of embolism identified by transesophageal echocardiography.

Embolic events have become a major indication for transesophageal echocardiography. We report three patients with cerebrovascular accident who were discovered to have retained left atrial catheter as a cardiac source of embolism. These radiolucent catheters, placed during previous cardiac surgery, were used for perioperative left atrial monitoring. Fracture of the catheter occurred during percutaneous removal after surgery. Subsequent identification was established by transesophageal echocardiography, which demonstrated a characteristic appearance of the catheter remnant within the left atrium. All patients underwent reoperation to remove the retained catheter and have had no recurrent embolic events. Although uncommon, retained catheter in the left atrium is an important potential source of systemic embolism. The diagnosis can be easily made with transesophageal echocardiography and should prompt surgical extraction of the catheter.

Aged↗
PubMed1998

Role of emergency intraoperative transesophageal echocardiography.

Transesophageal echocardiography (TEE) has a definitive role in the diagnosis and management of critically ill patients with cardiovascular disease and patients undergoing cardiac operations. The diagnostic role of emergency intraoperative TEE and the impact on clinical outcome have not been evaluated. We reviewed the indications, findings, and impact of emergency intraoperative TEE in 66 patients over a 4-year period. The indications for emergency TEE were unexplained hemodynamic instability (36 patients), preoperative evaluation of patients having emergency surgery (19 patients), cardiac evaluation of trauma cases (6 patients), and unexplained intraoperative hypoxemia (5 patients). New findings were disclosed in 53 (80%) patients, with an alteration of the planned surgical procedure in 15 (23%). Despite the therapeutic impact, 24 patients (36%) did not survive to hospital dismissal. We recommend that TEE be considered as the diagnostic tool of choice when surgical patients have unexplained hemodynamic instability, when time does not permit complete preoperative evaluation, when cardiovascular injury is suspected in a trauma patient, and to evaluate unexplained hypoxemia.

Adolescent↗
PubMed1998

Aneurysms in the left ventricular outflow tract: clinical presentation, causes, and echocardiographic features.

We present a descriptive compendium of anatomically interrelated aneurysms and aneurysmal-like structures arising in and around the left ventricular outflow tract. Images selected from the Mayo Clinic echocardiography database illustrate classic or typical examples of each entity. Essential morphologic features of each lesion are described. Clinical presentation, causes, and diagnostic echocardiographic features taken together can improve recognition and clinical management of this diverse group of anomalies.

Aortic Aneurysm↗
PubMed1998

HAIS (Hanil Alcohol Insight Scale): validation of an insight-evaluation instrument for practical use in alcoholism.

OBJECTIVE: Numerous studies on alcoholism treatment have indicated that there are many steps the alcoholic must take before he can be alcohol free, and the admission that he is an alcoholic is the first step towards that goal. This study concerns the validation of a 20-item questionnaire, for the objective evaluation of the insight status of alcoholics. METHOD: Alcoholic men (N = 58) were interviewed by three clinicians, and the decisions of all of the interviewers were concordant in categorizing 44 out of the 58 interviewees into three insight groups: poor, fair and good. Validation of the questionnaire was made against the 44 concordant categorizations. RESULTS: The assessments of the patient's insight state by these two different methods (the interview results and the scores of this scale) were found to be highly and significantly correlated (r = .79, p < .001). CONCLUSIONS: This scale may be useful for qualitative and quantitative evaluation of the insight of alcoholics, and may provide fundamental information in establishing different therapeutic strategies based on different insight states of the alcoholics in the recovery process.

Adult↗
PubMed1997

Aortic valve replacement for aortic stenosis with severe left ventricular dysfunction. Prognostic indicators.

BACKGROUND: Aortic valve replacement for aortic stenosis (AS) carries an increased risk in the presence of left ventricular (LV) systolic dysfunction. Few data are available on the outcome of such patients. METHODS AND RESULTS: Between 1985 and 1992, 154 consecutive patients (107 men and 47 women) with LV systolic dysfunction (ejection fraction [EF] < or = 35%) underwent aortic valve replacement for AS. The mean preoperative characteristics included EF, 27 +/- 6%; aortic valve mean gradient, 44 +/- 18 mm Hg; aortic valve area, 0.6 +/- 0.2 cm2; and cardiac output, 4.1 +/- 1.5 L/min. Simultaneous coronary artery bypass graft surgery was performed in 78 patients (51%). Perioperative (30-day) mortality was 9% (14 of 154 patients). Fifty patients died during follow-up. Coronary artery disease (P = .002) and a reduced preoperative cardiac output (P = .03) were significantly related to reduced overall survival rate by multivariate analysis. Postoperative improvement occurred in most patients; 88% were New York Heart Association class III or IV before surgery versus 7% after surgery. Postoperative EF was assessed in 76% of survivors; 76% of these demonstrated improvement. By multivariate analysis, change in EF was inversely related to coronary disease (P = .002) and preoperative aortic valve area (P = .03). CONCLUSIONS: Despite LV dysfunction, the risk of aortic valve replacement for AS was acceptable and related to coronary artery disease and mean aortic gradient, and long-term survival was related to coronary disease and cardiac output. Improvement in symptoms and EF occurred in most patients.

Adult↗
PubMed1997

Preload reduction to unmask the characteristic Doppler features of constrictive pericarditis. A new observation.

BACKGROUND: Respiratory variation of > or = 25% in mitral E velocity is a characteristic Doppler echocardiographic feature in constrictive pericarditis. However, a subset of patients with constriction do not exhibit the typical respiratory change, most likely because of marked increase in the left atrial pressure, and preload reduction may unmask the respiratory variation. METHODS AND RESULTS: In 12 patients with surgically confirmed constrictive pericarditis who had < 25% respiratory variation in mitral E velocity during an initial preoperative examination, the Doppler study was repeated after an attempt to decrease left ventricular filling pressure. At baseline, mean mitral E velocity was similar after inspiration and expiration (0.81 +/- 0.24 and 0.84 +/- 0.21 m/s, respectively). On repeat Doppler examination, with the patient in a head-up tilt or sitting position the decrease in mitral E velocity with inspiration (0.61 +/- 0.13 m/s) was significant (P < .004), whereas it did not change significantly with expiration. The mean percent respiratory change in E velocity was 5 +/- 7% at baseline and 32 +/- 28% with preload reduction. Eight (75%) of the 12 patients developed respiratory variation of > or = 25%. CONCLUSIONS: When the respiratory variation in Doppler mitral E velocity is blunted or absent during the evaluation of suspected constrictive pericarditis, repeat Doppler recording of mitral flow velocities after maneuvers to decrease preload is recommended to unmask the characteristic respiratory variation in mitral E velocity.

Echocardiography↗
PubMed1997

Aortic valve resistance in aortic stenosis: Doppler echocardiographic study and surgical correlation.

Four hundred seven patients with aortic stenosis who had Doppler echocardiography before surgery were studied to determine the feasibility of Doppler-derived valve resistance calculation and its clinical value. Patients with milder aortic stenosis had lower mean gradient, larger valve area, and lower maximal resistance than those with severe stenosis. Maximal resistance was related strongly to aortic stenosis severity but did not add any information after valve area and gradient were known and was not related to surgical mortality.

Aged↗
PubMed1997

Pericardial thickness measured with transesophageal echocardiography: feasibility and potential clinical usefulness.

OBJECTIVES: This study assessed the reliability of transesophageal echocardiographic measurements of pericardial thickness and the potential diagnostic usefulness of this technique. BACKGROUND: Transthoracic echocardiography cannot reliably detect thickened pericardium. The superior resolution achieved with transesophageal echocardiography should allow better pericardial definition. METHODS: Pericardial thickness measured at 26 locations in 11 patients with constrictive pericarditis who underwent intraoperative transesophageal echocardiography was compared with pericardial thickness measured with electron beam computed tomography. Intraobserver and interobserver variabilities were determined. Pericardial thickness was then measured in 21 normal subjects. With these values as a guide, two observers reviewed 37 transesophageal echocardiographic studies to determine whether echocardiographic measurement of pericardial thickness could be used to distinguish diseased from normal pericardium. RESULTS: The correlation between echocardiographic and computed tomographic measurements (r > or = 0.95, SE < or = 0.06 mm, p < 0.0001) was excellent. The +/-2 SD limits of agreement were +/-1.0 mm or less for pericardial thickness < 5.5 mm and +/-2.0 mm or less for the entire range of thicknesses. Intraobserver and interobserver agreements were good. Mean normal pericardial thickness was 1.2 +/- 0.8 mm (+/-2 SD) and did not exceed 2.5 mm. Pericardial thickness > or = 3 mm on transesophageal echocardiography was 95% sensitive and 86% specific for the detection of thickened pericardium. CONCLUSIONS: Measurement of pericardial thickness with transesophageal echocardiography is reproducible and should be a valuable adjunct in assessing constrictive pericarditis.

Case-Control Studies↗
PubMed1997

The noninvasive assessment of left ventricular diastolic function with two-dimensional and Doppler echocardiography.

Left ventricular diastolic filling can be determined reliably by Doppler-derived mitral and pulmonary venous flow velocities. Diastolic filling abnormalities are broadly classified at their extremes to impaired relaxation and restrictive physiology with many patterns in between. An impaired relaxation pattern identifies patients with early stages of heart disease, and appropriate therapy may avert progression and functional disability. Pseudonormalization is a transitional phase between abnormal relaxation and restrictive physiology and signifies increased filling pressure and decreased compliance. In this phase, reducing preload, optimizing afterload, and treating the underlying disease are clinically helpful. A restrictive physiology pattern identifies advanced, usually symptomatic disease with a poor prognosis. Therapeutic intervention is directed toward normalizing loading conditions and improving the restrictive filling pattern, although this may not be feasible in certain heart diseases. Finally, many patients have left ventricular filling patterns that appear indeterminate or mixed. In these cases, clinical information, left atrial and left ventricular size, pulmonary venous flow velocity, and alteration of preload help assess diastolic function and estimate diastolic filling pressures.

Adolescent↗
PubMed1997

Doppler evaluation of left and right ventricular diastolic function: a technical guide for obtaining optimal flow velocity recordings.

Doppler mitral flow velocities and related variables are used to assess left (LV) and right ventricular filling and, indirectly, ventricular diastolic function. Three abnormal ventricular filling patterns (impaired relaxation and pseudonormal and restrictive physiology) are recognized in patients with various heart diseases and have been related to alterations in LV diastolic properties and filling pressures. More recently, these variables have been used to assess the hemodynamic effects of drug therapy or heart surgery and prognosis in patients with restrictive and dilated cardiomyopathies. Despite these encouraging results, widespread clinical use of these Doppler techniques has been hampered by difficulties in obtaining accurate and reproducible measurements from Doppler flow velocity recordings. This is due, in part, to an underappreciation of factors such as cardiac filling mechanics, Doppler examination principles, and ultrasound machine settings, which can markedly affect the quality of the flow velocity recordings. The purpose of this article is to provide the technical information for performing a systematic and comprehensive Doppler evaluation of LV diastolic function that can be used on a routine basis. This information includes discussing the different flow velocity recordings required for a Doppler assessment of LV diastolic function, their proper recording technique, and the common technical pitfalls.

Blood Flow Velocity↗
PubMed1997

Is review of videotape necessary after review of digitized cine-loop images in stress echocardiography? A prospective study in 306 patients.

The interpretation of stress echocardiography has been made easier by the comparison of digitized prestress and poststress frame-grabbed images (cine-loops), each representing a portion of a single cardiac cycle. Often, review of these digitized images is substituted for review of the complete videotape record of the examination. An alternative is to review both the digitized images as well as the videotape record of the rest and stress images. To date, there has been insufficient documentation of whether these options (cine-loop images alone versus cine-loop images plus videotape) provide comparable or additive information. Therefore, we prospectively evaluated information obtained from review of cine-loop images versus combined review of cine-loop images and videotape records in 306 consecutive patients undergoing treadmill (213 patients, 70%) or dobutamine (93 patients, 30%) stress echocardiography. An experienced echocardiologist first reviewed the cine-loop images and scored the wall motion in 16 segments at rest and with stress. Next, the complete videotape record was reviewed with repeated wall motion scoring. A questionnaire comparing cine-loop and videotape images was completed at the end of each review. Digitization of images was technically inadequate in 14 patients (4%). In 116 (40%) of the other 292 patients, the regional wall motion assessment, after relying solely on cine-loop images, was modified with subsequent videotape review. In 40 patients (14%), these modifications resulted in a change in the final impression regarding whether the study result was normal or abnormal. In a multivariate analysis, age, gender, and type of stress echocardiography had no significant influence on discordance of the cine-loop image and combined cine-loop and video information. Stepwise logistic regression analysis identified poorer image quality (p < 0.0001) and regional wall motion abnormalities (p < 0.0001) as predictors of discordance between cine-loop and combined review. We conclude that relying solely on digitized cine-loop images representing a single cardiac cycle is not optimal, especially if the quality of the digitized images is suboptimal and if regional wall motion abnormalities are present. Thus we recommend a combined review of both cine-loop images and videotape images in the interpretation of stress echocardiography.

Aged↗
PubMed1997

Mycoplasma-associated pericarditis.

Mycoplasma pneumoniae-associated pericarditis may result in pronounced morbidity unless appropriate therapy is administered. In this report, we describe a patient who had recurrent episodes of chest pain, intermittent constitutional symptoms, and, eventually, cardiac tamponade due to pericarditis despite treatment with nonsteroidal anti-inflammatory drugs. Immunofluorescence antibody titers were consistent with recent M. pneumoniae infection, and antibiotic therapy resulted in rapid and complete resolution of the patient's symptoms. This treatable entity may be underrecognized and can now be diagnosed with sensitive serologic testing.

Diagnosis, Differential↗
PubMed1996

Diagnosis of sinus venosus atrial septal defect with transesophageal echocardiography.

BACKGROUND: Sinus venosus atrial septal defect (SVD) is underdiagnosed with transthoracic echocardiography because of its posterior (far field) location. Transesophageal echocardiography (TEE) should be ideally suited to diagnose SVD, given the proximity of the transducer to the defect. METHODS AND RESULTS: A retrospective study was undertaken that used the medical history, echocardiographic findings, and surgical data of patients identified from computer records as having the diagnosis of SVD during the period in which TEE has been in use (1987 to 1995). Twenty-five patients (14 females and 11 males; median age, 45 years; range, 10 to 75 years) with SVD had TEE between 1987 and 1995. Prior transthoracic echocardiography clearly defined the SVD in 3 of these patients, and it was suspected in another 11 on the basis of color-flow imaging. Ten patients had unexplained dilatation of the right side of the heart, which prompted TEE examination. SVD was visualized with TEE in all 25 patients and ranged in size from 1 to 3 cm. Thirty-seven right-sided anomalous pulmonary venous connections were identified in 23 patients. No left-sided anomalous pulmonary venous connections were detected. Anatomic confirmation was obtained in all 23 surgical patients. No patient required preoperative cardiac catheterization for diagnosis. CONCLUSIONS: TEE is accurate for the diagnosis of SVD and should be undertaken in any patient with unexplained dilatation of the right side of the heart. The associated pulmonary venous abnormalities can be identified with TEE. Cardiac catheterization for diagnostic purposes should not be required before surgical correction.

Adolescent↗
PubMed1996

Safety of performing dobutamine stress echocardiography in patients with abdominal aortic aneurysm > or = 4 cm in diameter.

Dobutamine stress echocardiography is frequently used for preoperative assessment of cardiac risk before major vascular surgical procedures. Dobutamine increases myocardial contractility, heart rate, and rate of increase of left ventricular pressure and has a variable effect on blood pressure. These effects could potentially increase the likelihood of rupture of a vascular aneurysm. The safety of performing dobutamine stress echocardiography in patients with vascular aneurysms has not been adequately addressed. Of 1,968 consecutive patients who underwent dobutamine stress echocardiography at our institution, 98 patients with abdominal aortic aneurysms > or = 4 cm in diameter were identified. Records were reviewed to determine whether there was any evidence of aneurysm rupture or adverse vascular events as a result of the stress test. There was no case of aneurysm rupture or hemodynamic instability precipitated by dobutamine stress echocardiography. In addition, dobutamine stress echocardiography that was negative for ischemia identified patients at very low risk of perioperative cardiac events. The positive predictive value of ischemia during dobutamine echocardiography was 29%. Dobutamine stress echocardiography may be performed safely in patients with aortic aneurysms. Precipitation of an aneurysmal complication, including rupture, by the test is unlikely. In addition, preoperative dobutamine stress echocardiography can identify patients at very low risk of perioperative cardiac events.

Aged↗
PubMed1996

Comparison of ischemic response during exercise and dobutamine echocardiography in patients with left main coronary artery disease.

OBJECTIVES: This study sought to compare manifestations of myocardial ischemia evoked by exercise and dobutamine echocardiography in patients with left main coronary artery disease. BACKGROUND: During exercise testing, left ventricular cavity dilation, marked ST segment depression and blood pressure decrease indicate severe coronary artery disease. Whether these signs are comparably evoked by dobutamine echocardiography has not been described. METHODS: Fifty-four patients who underwent stress echocardiography (36 exercise, 18 dobutamine) and coronary angiography showing > or = 50% left main stenosis were analyzed. Electrocardiographic and blood pressure changes, symptoms, wall motion score indexes and sensitivity for coronary artery disease were compared. In 47 patients, the left ventricular endocardium was traced to quantify volumes and ejection fraction. RESULTS: Stress-induced regional wall motion abnormalities developed in 91% of patients; this was not different on exercise (89%) or dobutamine echocardiography (94%). Rate-pressure product and wall motion score index, similar at rest, tended to be higher after exercise than after dobutamine stress (p = 0.07 and p = 0.05, respectively). ST segment depression > or = 1 mm was more common with exercise (p = 0.005). Ejection fraction and end-systolic and end-diastolic volume indexes were comparable at rest in both groups. With exercise, ejection fraction decreased in 87% of patients, and end-systolic and end-diastolic volume indexes increased in 80%. In contrast, with dobutamine, decreased ejection fraction and increased volume indexes were infrequent. Ejection fraction was lower ([mean +/- SD] 45 +/- 19% vs. 54 +/- 12%, p = 0.007) and end-diastolic (69 +/- 26 vs. 50 +/- 17 ml/m2, p =0.02) and end-systolic (39 +/- 20 vs. 24 +/- 13 ml/m2, p = 0.02) volume indexes were higher after exercise than after dobutamine stress. CONCLUSIONS: On the basis of changes in regional wall motion both dobutamine and exercise echocardiography have a comparable high sensitivity in diagnosing myocardial ischemia in left main coronary artery disease. However, conventional signs of severe myocardial ischemia, including left ventricular cavity dilation and marked ST segment depression, occur more often with exercise than with dobutamine echocardiography.

Aged↗
PubMed1996

Atropine augmentation in dobutamine stress echocardiography: role and incremental value in a clinical practice setting.

OBJECTIVES: This study sought to evaluate the role and incremental value of atropine in a large patient group undergoing dobutamine stress echocardiography. BACKGROUND: The use of atropine to potentiate dobutamine stress is not standard practice. Although the utility of atropine has been described, data on its incremental value remain limited and do not exist for a routine clinical practice setting. METHODS: Dobutamine stress echocardiography was performed in 1,171 patients with use of a standard protocol. Atropine (maximal dose 2.0 mg) was given to 299 patients (26%) who did not attain target heart rate. Coronary angiography was performed in 183 patients (46 received atropine), 148 of whom were found to have significant coronary artery disease (> or = 70% diameter stenosis in a major epicardial vessel, > or = 50% stenosis for left main coronary artery disease). All tests were reviewed independently by experienced observers. RESULTS: There were no major adverse events. Patients receiving atropine had a lower rest heart rate (65 vs. 74 beats/min, p < 0.0001) and more often received beta-adrenergic blocking agents (49% vs. 14%, p < 0.0001). Of 444 patients in whom stress-induced ischemia developed, 70 (16%) required atropine before ischemia became evident. Sensitivity for detection of significant coronary artery disease was 90% with dobutamine alone and 95% after the addition of atropine. In 66 patients with normal wall motion at rest, test sensitivity was 65% before and 84% after atropine was given. Atropine use did not compromise test specificity. New diagnostic information was obtained in 20 (50%) of 40 patients with angiographic coronary artery disease given atropine. Proportionately more patients with single-vessel disease required atropine before an ischemic response was observed; this effect appeared related to the higher ischemic threshold in these patients. CONCLUSIONS: Augmentation of heart rate had a modest influence on the overall diagnostic sensitivity of dobutamine stress echocardiography in our study cohort. However, it was particularly helpful in patients receiving beta-blockers and those with milder coronary disease. Despite the use of > or = 1 mg of atropine in some patients, this incremental value was not achieved at the expense of safety.

Adult↗