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J K Oh

Publications and source records attributed to J K Oh.

At least 37 records · Page 2Linked to original sources
PubMed1999

Constrictive pericarditis in the modern era: evolving clinical spectrum and impact on outcome after pericardiectomy.

BACKGROUND: The clinical spectrum of constrictive pericarditis (CP) has been affected by a change in incidence of etiological factors. We sought to determine the impact of these changes on the outcome of pericardiectomy. METHODS AND RESULTS: The contemporary spectrum of CP in 135 patients (76% male) evaluated at the Mayo Clinic from 1985 to 1995 was compared with that of a historic cohort. Notable trends were an increasing frequency of CP due to cardiac surgery and mediastinal radiation and presentation in older patients (median age, 61 versus 45 years). Perioperative mortality decreased (6% versus 14%, P = 0.011), but late survival was inferior to that of an age- and sex-matched US population (57+/-8% at 10 years). The long-term outcome was predicted independently by 3 variables in stepwise logistic regression analyses: (1) age, (2) NYHA class, and most powerfully, (3) a postradiation cause. Of 90 late survivors in whom functional class could be determined, functional status had improved markedly (2.6+/-0.7 at baseline versus 1.5+/-0.8 at latest follow-up [P<0.0001]), with 83% being free of clinical symptoms. CONCLUSIONS: The evolving profile of CP, with increasingly older patients and those with radiation-induced disease in the past decade, significantly affects postoperative prognosis. Long-term results of pericardiectomy are disappointing for some patient groups, especially those with radiation-induced CP. By contrast, surgery alleviates or improves symptoms in the majority of late survivors.

Adolescent↗
PubMed1999

Diagnosis and management of cardiac tamponade in the era of echocardiography.

Cardiac tamponade is a life-threatening condition. Accurate diagnosis and prompt intervention are necessary. Classically, clinical features of tamponade include pulsus paradoxus, tachycardia, increased jugular venous pressure, and hypotension. With the advent of echocardiography, confirmation of an effusion and accurate assessment of its hemodynamic impact can be achieved, frequently in the absence of overt clinical manifestations. The decision regarding treatment and timing of intervention must take into account the clinical presentation and echocardiographic findings, along with careful weighing of risks and benefits to the individual patient. Echocardiographically guided pericardiocentesis is the best available therapy for initial management of cardiac tamponade. It is simple, safe, and effective for removing pericardial fluid and reversing hemodynamic instability, and the use of a pericardial catheter for extended drainage has been associated with significant reduction in recurrence of fluid accumulation.

Cardiac Tamponade↗
PubMed1999

Left ventricular systolic and diastolic function after pericardiectomy in patients with constrictive pericarditis: Doppler echocardiographic findings and correlation with clinical status.

OBJECTIVES: The study assessed changes in left ventricular systolic and diastolic function after pericardiectomy in patients with constrictive pericarditis and correlated postoperative Doppler echocardiographic findings with clinical status. BACKGROUND: Despite the efficacy of pericardiectomy, some patients with constrictive pericarditis fail to improve postoperatively. Data on serial evaluation of systolic and diastolic function after pericardiectomy and its relation to clinical status are not available. METHODS: From 1985 to 1995, a total of 58 patients with constrictive pericarditis underwent pericardiectomy and had at least one follow-up Doppler echocardiographic study with a respirometer: 23 patients had one examination within 3 months postoperatively, 19 had a study within 3 months and another one more than 3 months postoperatively, and 16 had one study more than 3 months postoperatively. RESULTS: In the early postoperative period, diastolic function was normal in 17 patients (40.5%), restrictive in 17 (40.5%), and constrictive in 8 (19%). Among 19 patients who had serial Doppler echocardiography, in 2 patients with restrictive physiology and 5 with constrictive physiology the results had become normal, and 1 patient who had had constrictive physiology had restrictive findings. In late follow-up, left ventricular end-diastolic diameter increased compared with preoperative measurement (p = 0.0009). Diastolic filling pattern at late follow-up was normal in 20 patients (57%), restrictive in 12 (34%) and constrictive in 3 (9%). There was a significant relationship between diastolic filling patterns and symptomatic status (chi2 = 20.9, p < 0.0001). Patients with persistent abnormal diastolic filling on Doppler echocardiography had had symptoms for a longer time preoperatively than did patients with normal diastolic physiology (p = 0.0471). CONCLUSIONS: Diastolic filling characteristics remain abnormal in a substantial number of patients with constrictive pericarditis after pericardiectomy. These abnormalities may resolve gradually but can persist. Diastolic filling abnormalities after pericardiectomy correlate well with clinical symptoms and tend to occur in patients who have had symptoms longer preoperatively. This finding supports the recommendation that pericardiectomy be performed promptly in symptomatic patients with constrictive pericarditis.

Adolescent↗
PubMed1999

One or two lag screws for fixation of Danis-Weber type B fractures of the ankle.

BACKGROUND: There are many limitations in using the plate for fixation of lateral malleolar fractures of the ankle. METHODS: This study prospectively reviewed 60 of 72 consecutive patients with an average follow up of 3.8 years who had Danis-Weber type B ankle fractures that were treated with one or two 3.5-mm cortical lag screws without plate fixation. RESULTS: A stable anatomic reduction was obtained in 57 cases (95%). The average time to healing by radiograph was 3.1 months. There were two delayed unions and no nonunions. Joint space narrowing was found in one case. Clinical assessment was satisfactory in 56 of the patients (93%). CONCLUSION: Noncomminuted Danis-Weber Type B ankle fractures can be successfully treated without the risk of lateral plating, which includes cartilage damage caused by penetration of the ankle joint, increased periosteal dissection, and the risk of subsequent hardware removal.

Adult↗
PubMed1999

Effect of various ions, pH, and osmotic pressure on oxidation of elemental sulfur by Thiobacillus thiooxidans.

The oxidation of elemental sulfur by Thiobacillus thiooxidans was studied at pH 2.3, 4.5, and 7.0 in the presence of different concentrations of various anions (sulfate, phosphate, chloride, nitrate, and fluoride) and cations (potassium, sodium, lithium, rubidium, and cesium). The results agree with the expected response of this acidophilic bacterium to charge neutralization of colloids by ions, pH-dependent membrane permeability of ions, and osmotic pressure.

Acidithiobacillus thiooxidans↗
PubMed1999

Intracardiac leiomyomatosis: echocardiographic features.

Intravenous leiomyomatosis is a histologically benign smooth-muscle tumor arising from either a uterine myoma or the walls of a uterine vessel with extension into veins. Echocardiographic features of two cases of intravenous leiomyomatosis with extensive spread into the right-sided cardiac chambers and pulmonary arteries are described. Both patients were middle-aged women, with prior history of hysterectomy 12 and 10 years earlier who presented with cardiac symptoms and signs. Distinctive echocardiographic features include 1) elongated mobile masses extending from the veins of the lower body, including inferior vena cava and azygos vein; 2) multiple venous attachments or metastases; and 3) filling of venous vessels and right-heart chambers. Intracardiac leiomyomatosis should be considered in a female patient presenting with an extensive mass in the right-sided cardiac chambers.

Echocardiography, Transesophageal↗
PubMed1999

Constrictive pericarditis and pleuropulmonary disease linked to ergot dopamine agonist therapy (cabergoline) for Parkinson's disease.

Cabergoline is one of several ergoline dopamine agonist medications used in the treatment of Parkinson's disease (PD). We diagnosed constrictive pericarditis (CP) in a patient with PD receiving cabergoline therapy (10 mg daily), who had symptoms and signs of congestive heart failure (CHF). In the absence of previous reported cases of this condition linked to ergoline drugs, cabergoline was not initially identified as the cause. Shortly thereafter, however, the patient developed of a severe pleuropulmonary inflammatory-fibrotic syndrome, a recognized complication of ergoline medications, thus suggesting a common pathogenesis due to cabergoline therapy. To our knowledge, this is the first case in the English literature, although we speculate that CP may be more common than reported among patients with PD who are treated with an ergoline drug (cabergoline, bromocriptine, pergolide, or lisuride). The diagnosis of CP is difficult and requires a high level of suspicion; symptoms may masquerade as CHF due to common mechanisms such as coronary artery disease. In patients with PD who are taking not only cabergoline but also one of the other ergoline drugs, CP should be suspected if symptoms of CHF develop.

Aged↗
PubMed1999

Dynamic left ventricular outflow tract obstruction in acute coronary syndromes: an important cause of new systolic murmur and cardiogenic shock.

Dynamic left ventricular outflow tract (LVOT) obstruction has traditionally been associated with hypertrophic obstructive cardiomyopathy. Recently, acute dynamic LVOT obstruction has been described as a complication of myocardial infarction (MI). Herein the cases of 3 patients are described, all of whom presented with a systolic murmur and electrocardiographic evidence of MI. All 3 patients developed cardiogenic shock and were subsequently found by echocardiography to manifest an acute dynamic LVOT obstruction. Cardiogenic shock persisted until therapy was directed toward decreasing the degree of the dynamic LVOT obstruction. The treatment of acute coronary syndromes in the presence of a dynamic LVOT obstruction differs from the traditional treatment of acute coronary syndromes and includes the use of beta-blockers and alpha1-agonists, as well as the avoidance of therapies that aggravate the magnitude of the LVOT obstructive gradient, including nitrates, inotropic agents, and afterload reduction. The development of a systolic murmur in the setting of acute MI complicated by cardiogenic shock with only a small elevation in creatine kinase suggests the presence of a dynamic LVOT obstruction, as well as the classical mechanical complications of MI, namely, ventricular septal rupture and papillary muscle rupture. The presence of a dynamic LVOT obstruction is reliably detected by transthoracic echocardiography or by transesophageal echocardiography if transthoracic image quality is suboptimal.

Aged↗
PubMed1998

Chronotropic response, safety, and accuracy of dobutamine stress echocardiography in patients with atrial fibrillation and known or suspected coronary artery disease.

Ninety-two consecutive patients with atrial fibrillation (AF) who underwent dobutamine stress echocardiography were compared with a control group of patients in sinus rhythm matched for age, sex, and resting heart rate. Patients with AF had an increased chronotropic response to dobutamine, but there were no adverse effects and no evidence that the lower doses of dobutamine typically given to patients with AF were insufficient to induce ischemia.

Adrenergic beta-Antagonists↗
PubMed1998

Clinical profile and outcome in 52 patients with cardiac pseudoaneurysm.

BACKGROUND: Cardiac pseudoaneurysm, a contained cardiac rupture, predisposes patients to further rupture. However, knowledge of the clinical profile and natural history of this cardiac complication is limited. OBJECTIVE: To study the clinical features and outcomes of patients with cardiac pseudoaneurysm. DESIGN: Retrospective analysis of patients with cardiac pseudoaneurysm seen between January 1980 and September 1996. SETTING: Mayo Clinic in Rochester, Minnesota; Scottsdale, Arizona; and Jacksonville, Florida. PATIENTS: 52 patients with pseudoaneurysm. RESULTS: Pseudoaneurysm was discovered incidentally in 25 asymptomatic patients (48%). Four patients (8%) presented acutely (3 with acute myocardial infarction and 1 with cardiac tamponade). Other clinical presentations were congestive heart failure in 8 patients (15%), chest pain in 7 (13%), syncope or arrhythmia in 5 (10%), and systemic embolism in 3 (6%). Initial diagnostic tests were echocardiography in 32 patients, cardiac catheterization in 12, magnetic resonance imaging in 4, and computed tomography in 2. Diagnosis was made intraoperatively in two patients. Pseudoaneurysm occurred after cardiac surgery in 30 patients (58%) and after myocardial infarction in 22 (42%). Location of the pseudoaneurysm was primarily related to its cause: Pseudoaneurysm was located in the inferior or posterolateral wall in 18 of 22 patients (82%) after myocardial infarction, in the right ventricular outflow tract in 13 of 15 patients (87%) after congenital heart surgery, in the posterior subannular region of the mitral valve in 4 of 4 patients (100%) after mitral valve replacement, and in the subaortic region in 3 of 3 (100%) after aortic valve replacement. Forty-two patients (81%) had surgical repair (surgical mortality rate, 7%). Ten patients (19%) did not have surgery. Nineteen patients died after a median survival of 2.3 years (range, 3 days to 8.2 years): Eight died of noncardiac cause, 5 of congestive heart failure, 4 of acute myocardial infarction, and 2 of cardiac arrhythmia (ventricular tachycardia). No further cardiac ruptures were documented. CONCLUSIONS: A substantial number of patients with pseudoaneurysm are asymptomatic. Although surgical repair is the treatment of choice, conservative management in selected patients with increased surgical risk seems reasonable because no deaths were caused by further rupture.

Adult↗
PubMed1998

Outcome after normal exercise echocardiography and predictors of subsequent cardiac events: follow-up of 1,325 patients.

OBJECTIVES: This study sought to examine the outcome of a large group of patients after normal exercise echocardiography and to identify potential predictors of subsequent cardiac events. BACKGROUND: Earlier studies suggested that prognosis after normal exercise echocardiography is favorable, with a low subsequent cardiac event rate. These studies involved a small number of patients and did not have sufficient statistical power to stratify risk. METHODS: The outcomes of 1,325 patients who had normal exercise echocardiograms were examined. End points were overall and cardiac event-free survival. Cardiac events were defined as cardiac death, nonfatal myocardial infarction and coronary revascularization. Patient characteristics were analyzed in relation to time to first cardiac event in a univariate and multivariate manner to determine which, if any, were associated with an increased hazard of subsequent cardiac events. RESULTS: Overall survival of the study group was significantly better than that of an age- and gender-matched group obtained from life tables (p < 0.0001). The cardiac event-free survival rates at 1, 2 and 3 years were 99.2%, 97.8% and 97.4%, respectively. The cardiac event rate per person-year of follow-up was 0.9%. Subgroups with an intermediate or high pretest probability of having coronary artery disease also had low cardiac event rates. Multivariate predictors of subsequent cardiac events were angina during treadmill exercise testing (risk ratio [RR] 4.1, 95% confidence interval [CI] 1.5 to 11.0), low work load (defined as < 7 metabolic equivalents [METs] for men and < 5 METs for women; RR 3.2, 95% CI 1.4 to 7.6), echocardiographic left ventricular hypertrophy (RR 2.6, 95% CI 1.1 to 6.3) and advancing age (RR 1.04/year, 95% CI 1.0 to 1.1). CONCLUSIONS: The outcome after normal exercise echocardiography is excellent. Subgroups with an intermediate or high pretest probability of having coronary artery disease also have a favorable prognosis after a normal exercise echocardiogram. Characteristics predictive of subsequent cardiac events (i.e., patient age, work load, angina during exercise testing and echocardiographic left ventricular hypertrophy) should be considered in the clinical interpretation of a normal exercise echocardiogram.

Aged↗
PubMed1998

Myocardial viability during dobutamine echocardiography predicts survival in patients with coronary artery disease and severe left ventricular systolic dysfunction.

OBJECTIVES: The purpose of this study was to assess whether the presence or absence of myocardial viability during dobutamine echocardiography (DE) predicts survival in patients with coronary artery disease (CAD) and severe left ventricular (LV) dysfunction. BACKGROUND: In patients with CAD, the presence of myocardial viability during DE identifies viable myocardium and predicts recovery of LV systolic function after revascularization. However, there is little data on the relation between myocardial viability and clinical outcome in patients with CAD and severe LV dysfunction. METHODS: We studied 318 patients with CAD and a LV ejection fraction (EF) < or =35% who underwent DE and were followed for 18+/-10 months. Patients were classified into four groups. Group I (n=85) consisted of patients who had evidence of myocardial viability and subsequently underwent revascularization. Group II (n=119) consisted of patients with myocardial viability who did not undergo revascularization. Group III (n=30) consisted of patients who did not have myocardial viability and underwent revascularization. Finally, group IV (n=84) patients lacked myocardial viability and did not undergo revascularization. RESULTS: The four groups had similar baseline characteristics and rest LVEF. During follow-up there were 51 deaths (16%). The mortality rate was 6% in group I, 20% in group II, 17% in group III and 20% in group TV (p=0.01, group I vs. other groups). CONCLUSIONS: In patients with CAD and severe LV dysfunction who demonstrated myocardial viability during DE, revascularization improved survival compared with medical therapy.

Aged↗
PubMed1998

Comparison of mitral inflow and superior vena cava Doppler velocities in chronic obstructive pulmonary disease and constrictive pericarditis.

OBJECTIVE: This study was conducted to determine whether Doppler recording of superior vena cava flow velocities can differentiate chronic obstructive pulmonary disease from constrictive pericarditis in patients with a respiratory variation of > or = 25% in mitral inflow E velocity. BACKGROUND: Although respiratory variation (> or = 25%) in mitral E velocity is the main diagnostic criterion for constrictive pericarditis by Doppler echocardiography, it can also be present in chronic obstructive pulmonary disease. Because the respiratory variation is due to increased change in intrathoracic pressure with respiration in chronic obstructive pulmonary disease, and to dissociation of intrathoracic-intracardiac pressure changes in constriction, it was hypothesized that the Doppler flow velocity pattern in the superior vena cava (affected by intrathoracic pressure) would be different in these two conditions. METHODS: Pulsed-wave Doppler recording of mitral and superior vena cava flow velocities in 20 patients with chronic obstructive pulmonary disease who had > or = 25% respiratory variation in mitral E-wave velocity were compared with those of 20 patients who had surgically proved constrictive pericarditis. RESULTS: Constrictive pericarditis and chronic obstructive pulmonary disease had similar respiratory variation in mitral E velocity (41% versus 46%). In the latter, the E/A ratio was lower (inspiration, 0.8+/-0.3 versus 1.5+/-0.7 [p < 0.0001]; expiration, 1.0+/-0.3 vs. 1.9+/-0.7 [p < 0.0001]) and deceleration time longer (inspiration, 198+/-53 ms versus 137+/-32 ms; expiration, 225+/-43 ms vs. 161+/-33 ms [p < 0.0001]). Inspiratory superior vena cava systolic forward flow velocity was significantly higher in chronic obstructive pulmonary disease (72.9+/-22.6 cm/s versus 36.2+/-9.3 cm/s, p < 0.0001), while expiratory systolic forward flow velocity was similar. Hence, there was a significantly greater respiratory variation in superior vena cava systolic forward flow velocity in chronic obstructive pulmonary disease without an overlap with constrictive pericarditis (39.5+/-18.8 cm/s vs. 4.2+/-3.4 cm/s, p < 0.0001). CONCLUSIONS: Despite a similar respiratory variation in mitral E wave velocities, mitral inflow variables in chronic obstructive pulmonary disease are less restrictive compared with those in constrictive pericarditis. More importantly, patients with chronic obstructive pulmonary disease show a marked increase in inspiratory superior vena cava systolic forward flow velocity, which is not seen in patients with constrictive pericarditis.

Aged↗
PubMed1998

Short deceleration time of mitral inflow E velocity: prognostic implication with atrial fibrillation versus sinus rhythm.

The present study retrospectively identified 367 patients who had restrictive physiology as defined by deceleration time < or = 130 msec; 293 were in sinus rhythm (SR) (194 men and 99 women; mean age 64 +/- 14 years) and 74 were in atrial fibrillation (AF) (51 men and 23 women; mean age 72 +/- 11 years; p < 0.001). Both groups had similar underlying diagnoses and no significant difference in Doppler indices (E wave, 96 +/- 23 vs 99 +/- 22 cm/sec in SR and AF, respectively; deceleration time, 116 +/- 12 vs 116 +/- 13 msec; and left ventricular outflow tract time velocity integral, 14.8 +/- 4.8 vs 14.5 +/- 4.4 cm). Left ventricular ejection fraction was significantly lower in SR patients (29% +/- 16% vs 39% +/- 20%; p = 0.0003). There were 120 deaths (41%) in the SR group and 35 (47%) in the AF group (median follow-up for both groups, 2.2 years). Restrictive physiology as defined by Doppler echocardiography (deceleration time < or = 130 msec) appears to predict a similar poor prognosis with AF as with SR.

Aged↗
PubMed1998

Role of intraoperative transesophageal echocardiography in determining aortic annulus diameter in homograft insertion.

The sizing of aortic valve (AV) homografts for optimum function requires an accurate measurement of the aortic annulus. Typically, this measurement is obtained directly with sizers in the open aorta. We describe the use of intraoperative transesophageal echocardiography (IOTEE) to measure the aortic annulus and select the appropriate AV homograft before cardiopulmonary bypass and aortic cross-clamping. Thirty-two patients underwent AV homograft insertion between March 1993 and March 1996 and had IOTEE. There were 13 women and 19 men. Mean age was 58 +/- 14 years. IOTEE measurements were satisfactory in sizing in all patients, and no extraordinary surgical measures were necessary to insert the AV homografts. Early postoperative follow-up showed trivial or mild regurgitation of all homografts. Prebypass IOTEE is reliable in guiding the selection of optimal AV homografts.

Adult↗