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Jae K Oh

Publications and source records attributed to Jae K Oh.

64 records · Page 4Linked to original sources
PubMed2002

Chronobiological patterns of acute aortic dissection.

BACKGROUND: Chronobiological rhythms have been shown to influence the occurrence of a variety of cardiovascular disorders. However, the effects of the time of the day, the day of the week, or monthly/seasonal changes on acute aortic dissection (AAD) have not been well studied. METHODS AND RESULTS: Accordingly, we evaluated 957 patients enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2000 (mean age 62+/-14 years, type A 61%). A chi2 test for goodness of fit and partial Fourier analysis were used to evaluate nonuniformity and rhythmicity of AAD during circadian, weekly, and monthly periods. A significantly higher frequency of AAD occurred from 6:00 AM to 12:00 noon compared with other time periods (12:00 noon to 6:00 PM, 6:00 PM to 12:00 midnight, and 12:00 midnight to 6:00 AM; P<0.001 by chi2 test). Fourier analysis showed a highly significant circadian variation (P<0.001) with a peak between 8:00 AM and 9:00 AM. Although no significant variation was found for the day of the week, the frequency of AAD was significantly higher during winter (P=0.008 versus other seasons by chi2 test). Fourier analysis confirmed this monthly variation with a peak in January (P<0.001). Subgroup analysis identified a significant association for all subgroups with circadian rhythmicity. However, seasonal/monthly variations were observed only among patients aged <70 years, those with type B AAD, and those without hypertension or diabetes. CONCLUSIONS: Similar to other cardiovascular conditions, AAD exhibits significant circadian and seasonal/monthly variations. Our findings may have important implications for the prevention of AAD by tailoring treatment strategies to ensure maximal benefits during the vulnerable periods.

Aged↗
PubMed2002

Severe pulmonary hypertension in patients with severe aortic valve stenosis: clinical profile and prognostic implications.

OBJECTIVES: We analyzed the clinical characteristics and outcomes of 47 patients with severe pulmonary hypertension (PHT) and severe aortic valve stenosis (AS) from 1987 to 1999. BACKGROUND: The prognostic implications of severe pulmonary hypertension in patients with severe AS are poorly understood. METHODS: The mean age of patients was 78 years (range 47 to 91 years), and 37 patients (79%) were in New York Heart Association (NYHA) functional class III or IV. Aortic valve replacement (AVR) was performed in 37 patients (79%) and 10 patients (21%) were treated conservatively. RESULTS: In the group that had AVR, there were six perioperative deaths (16%) and nine late deaths, resulting in a total mortality of 32%. In the conservatively treated group, there were eight deaths (80%) on follow-up. Severe PHT was an independent predictor of perioperative mortality. However, perioperative mortality was independent of the severity of left ventricular systolic dysfunction or concomitant coronary artery bypass grafting. Aortic valve replacement was associated with significant improvement in left ventricular ejection fraction, the severity of PHT and NYHA functional class. The difference between long-term survival of the operative survivors and the expected survival from life tables was not statistically significant. CONCLUSIONS: The prognosis for patients with AS and severe PHT treated conservatively without AVR is dismal. Although AVR is associated with higher than usual mortality, the potential benefits outweigh the risk of surgery.

Aged↗
PubMed2002

Intracardiac phased-array imaging: methods and initial clinical experience with high resolution, under blood visualization: initial experience with intracardiac phased-array ultrasound.

OBJECTIVES: This study was designed to test the feasibility of high-resolution phased-array intracardiac imaging. BACKGROUND: Intracardiac echocardiographic imaging of the heart during interventional electrophysiologic (EP) procedures has been limited by inadequate ultrasound penetration and absence of Doppler hemodynamic and flow information produced by rotating mechanical ultrasound elements. METHODS: A 10F (3.2 mm) phased-array, variable 5.5 to 10 MHz frequency imaging catheter with a four-way deflectable tip was applied in 24 patients undergoing EP studies. Sixteen prespecified cardiac targets were imaged from a right heart venue. RESULTS: Fifteen patients had no underlying organic heart disease; nine had ischemic, cardiomyopathic, valvular or congenital heart disorders. Longitudinal and short-axis imaging readily disclosed each cardiac valve, support structures and chamber, as well as the pericardium, right and left atrial appendages, the junction of the right atrium and superior vena cava, crista terminalis, tricuspid valve isthmus, coronary sinus orifice, membranous fossa ovalis and pulmonary veins. The average target depth was 8.8+/-1.5 cm (range 0.5 to 15 cm), with adequate penetration at a 7.5 MHz imaging frequency. Color flow and Doppler utilities clearly characterized transaortic and pulmonic valve and pulmonary vein blood flow, including during low output states. CONCLUSIONS: These first human studies with this technology demonstrate the methods, feasibility and utility of intracardiac phased-array vector and Doppler imaging for long-axis, apex-to-base global cardiac imaging. High resolution of endocardial structures and catheters suggests additional utility for visualizing interventional procedures from the right heart.

Arrhythmias, Cardiac↗
PubMed2002

Hypertensive response to exercise: a potential cause for new wall motion abnormality in the absence of coronary artery disease.

OBJECTIVES: We sought to characterize patients with a hypertensive response during exercise echocardiography and its effect on results of the test. BACKGROUND: A hypertensive response to exercise has been shown to cause false-positive results in perfusion imaging, radionuclide angiography and exercise electrocardiography, but its influence on exercise echocardiography has not been reported. METHODS: We identified 548 of 6,686 patients who had coronary angiography within four weeks after exercise echocardiography from 1992 through 1996. Echocardiographic results from 132 patients (24%) with a hypertensive response to exercise, defined as systolic blood pressure (SBP) >220 mm Hg for men and SBP >190 mm Hg for women or as an increase in diastolic blood pressure (DBP) >10 mm Hg or DBP >90 mm Hg during exercise echocardiography, were compared with those from 416 patients without a hypertensive response. RESULTS: Of 132 patients with a hypertensive response to exercise, 108 patients had exercise echocardiographic results positive for ischemia. Of these patients, 24 (22%) were found to have no significant coronary artery disease (CAD). In contrast, of 320 patients with positive exercise echocardiographic results without a hypertensive response, 39 (12%) patients did not have significant CAD. Among the false-positive results, new wall motion abnormalities were extensive in 15 of 24 (63%) hypertensive responders involving >25% of segments compared with 14 of 39 non-hypertensive responders (36%, p = 0.012). CONCLUSIONS: An excessive rise in blood pressure during exercise is associated with a greater likelihood of new or worsening abnormalities with exercise, which may be observed in the absence of angiographically significant coronary artery stenosis.

Aged↗
PubMed2002

Cardiac amyloidosis presenting with elevations of cardiac troponin I and angina pectoris.

We present the case of a 43-year-old male who was initially evaluated for angina pectoris and dyspnea. His CK, CK-MB, and cTnI were all elevated following a blood transfusion and he underwent coronary arteriography, which demonstrated no luminal obstructions. After several months, he was transferred to Mayo Clinic where diagnoses of fulminant cardiac amyloidosis and systemic multiple myeloma were established. The cTnI remained elevated despite normalization of the CK and CK-MB. Despite aggressive treatment, the patient died. Postmortem analysis demonstrated amyloid cardiac deposition including involvement of the coronary microvasculature. Electron microscopy revealed myocyte compression injury from amyloid infiltration. We believe this is the first report of elevated troponin I in a patient with cardiac amyloidosis. The electron microscopy in our case confirms cardiac damage as the mechanism for cTnI elevation. This observation strengthens our knowledge about the specificity of cTnI for the detection of cardiac injury.

Adult↗
PubMed2002

Myocardial viability independently influences left ventricular diastolic function in the early phase after acute myocardial infarction.

BACKGROUND: After acute myocardial infarction, a broad range of left ventricular (LV) end-diastolic pressure (LVEDP) is expected because of chamber remodeling. However, intrinsic characteristics of the infarcted tissue (necrosis or viability) may also play a role. We aimed to evaluate whether myocardial viability (Mviab) has an influence on LVEDP. METHODS: One hundred twenty-three consecutive patients with acute myocardial infarction underwent low-dose dobutamine echocardiography (5-10 microg/kg/min) to assess Mviab. Mviab was quantitatively evaluated by the variation of Delta wall motion score index. Patients underwent left heart catheterization with recording of LVEDP and a complete echocardiographic examination with measurement of LV volumes, ejection fraction, and mass. RESULTS: The overall population (81% male; mean age 58 +/- 10 years) was divided into 2 groups according to the presence (group 1; 66 patients) or absence (group 2; 57 patients) of Mviab. LVEDP was higher in patients without Mviab (16 +/- 8 vs 20 +/- 7 mm Hg; P =.02). The multivariate analysis showed that Delta wall motion score index correlated with LVEDP (P =.01) independent of wall motion score index and LV end-systolic volume. CONCLUSIONS: After acute myocardial infarction, LVEDP shows wide variability and is independently associated with Mviab.

Female↗
PubMed2002

Diagnostic value of mitral annular velocity for constrictive pericarditis in the absence of respiratory variation in mitral inflow velocity.

Respiratory variation of 25% or more in transmitral early diastolic filling (E) velocity is a well-recognized diagnostic feature of constrictive pericarditis (CP) that is useful for distinguishing it from restrictive cardiomyopathy. However, a subset of patients with CP do not exhibit the typical respiratory change. Recent data showed that mitral annular (E') velocity measured by Doppler tissue echocardiography (DTE) is markedly reduced in patients with restrictive cardiomyopathy whereas E' velocity is well-preserved in CP. This study evaluated the role of DTE for the diagnosis of CP when there is no characteristic respiratory variation of E velocity. From September 1999 to March 2001, 19 patients (17 men, 2 women; mean age, 57 +/- 13 years) with surgically confirmed CP underwent comprehensive echocardiography preoperatively, including pulsed wave and DTE examination with simultaneous recording of respiration. Nine (47%) of the 19 patients had less than 25% respiratory variation in E velocity. There was no significant difference in mitral inflow peak velocity, deceleration time, early-to-late ventricular filling ratio, and E' velocity between patients with and patients without respiratory variation of E velocity of 25% or more. Regardless of the presence or absence of a significant respiratory variation of E velocity, E' velocity was relatively normal (mean, 12 +/- 4 cm/s) in all patients with CP. In conclusion, E' velocity is well preserved in patients with isolated CP even when there is no characteristic respiratory variation of E velocity. Thus, when the respiratory variation in Doppler E velocity is blunted or absent during the evaluation of suspected CP in patients with restrictive mitral inflow velocity, preserved E' velocity shown by DTE should support the diagnosis of CP over a primary myocardial disease.

Adult↗
PubMed2002

Constrictive pericarditis in chronic ulcerative colitis.

Acute pericarditis has been described as an extraintestinal manifestation of inflammatory bowel disease (IBD), as well as a consequence of IBD treatment, specifically sulfasalazine and mesalamine. Until now, there have been no reported cases of constrictive pericarditis associated with IBD or its treatment. A 37-year-old woman with a 24-year history of chronic ulcerative colitis (CUC) presented with a 3-month history of fevers, palpitations, dyspnea, syncope, and retrosternal chest pain. Two weeks before symptoms, she had initiated oral mesalamine for an ongoing CUC flare. Physical examination suggested constrictive pericarditis. An echocardiogram revealed a thickened pericardium with a nearly circumferential fibrinous effusion, with Doppler confirming diastolic compromise. The patient proceeded to radical pericardectomy. Pathological examination showed grossly hemorrhagic acute and chronic pericarditis, with cultures and cytology negative. To date, only 104 cases of IBD with acute pericarditis have been reported, with fewer than 10 cases of mesalamine-induced acute pericarditis reported. This is the first reported case of constrictive pericarditis related to IBD or its treatment. Although our patient may have had IBD-associated constrictive pericarditis, her mesalamine use raises the possibility of a drug-induced constrictive pericarditis.

Adult↗