Ming-Shyan Chern

Short- and long-term results of catheter balloon percutaneous transvenous mitral commissurotomy

Percutaneous transvenous mitral commissurotomy (PTMC) was performed in 219 patients with symptomatic, severe rheumatic mitral stenosis. There were 59 men and 160 women, aged 19 to 76 years (mean 43). Pliable, noncalcified valves were present in 139 (group 1), and calcified valves or severe mitral subvalvular lesions, or both, in 80 patients (group 2). Atrial fibrillation was present in 133 patients (61%) and 1+ or 2+ mitral regurgitation in 59 (27%). Technical failure occurred with 3 patients in our early experience. There was no cardiac tamponade or emergency surgery. The only in-hospital death occurred 3 days after the procedure in a group 2 premoribund patient in whom last-resort PTMC created 3+ mitral regurgitation. Mitral regurgitation appeared or increased in 72 patients (33%); 3+ mitral regurgitation resulted in 12 patients (6%). There were 3 systemic embolisms. Atrial left-to-right shunts measured by oximetry developed in 33 patients (15%). Immediately after PTMC, there were significantly reduced (p = 0.0001) left atrial pressure (24.2 +/- 5.6 to 15.1 +/- 5.1 mm Hg), mean pulmonary artery pressure (39.7 +/- 13.0 to 30.6 +/- 10.9 mm Hg) and mitral valve gradient (13.0 +/- 5.1 to 5.7 +/- 2.6 mm Hg). Mitral valve area increased from 1.0 +/- 0.3 to 2.0 +/- 0.7 cm2 (p = 0.0001) and cardiac output from 4.4 +/- 1.4 to 4.7 +/- 1.2 liters/min (p less than 0.01). The results mirrored clinical improvements in 209 patients (97%). Multivariate analysis showed an echo score greater than 8, and valvular calcification and severe subvalvular lesions as independent predictors for suboptimal hemodynamic results.(ABSTRACT TRUNCATED AT 250 WORDS)

Multiplane transesophageal echocardiography in the diagnosis of congenital coronary artery fistula

The purpose of this study was to examine the advantages of multiplane transesophageal echocardiography in the diagnosis of congenital coronary artery fistula, specifically in depicting the origin, the course, and the drainage site. Seven consecutive patients ranging in age from 20 to 72 years with a suspected coronary artery fistula underwent conventional transthoracic and multiplane transesophageal echocardiographic studies between March 1993 and July 1994. When a coronary artery fistula was noted, the origin, the course, and the drainage site were carefully searched for. All patients then underwent a cardiac catheterization with the performance of coronary angiography. A large right coronary artery fistula was detected in three patients; one of them had a drainage to the posterior left ventricle, one to the lateral right ventricle, and the other to the medial aspect of the right ventricle just below the insertion of the septal leaflet of the tricuspid valve. A small coronary artery fistula arising from the left coronary artery was noted in four patients, two from the left anterior descending artery and the other two from the left circumflex artery. Three of these four patients had a drainage to the main pulmonary artery and one to the left ventricle. The drainage site was clearly depicted in all seven patients, whereas the origin and the course were precisely defined in five patients by using multiplane transesophageal echocardiographic examination. The multiplane transesophageal echocardiography provides a panoramic view of the coronary artery and the fistulous vessel with a precise definition of the origin, the course, and the drainage site of the fistula. Therefore it is the noninvasive diagnostic mode of choice.

Increased frequency of apolipoprotein B signal peptide sp24/24 in patients with coronary artery disease. General allele survey in the population of Taiwan and comparison with Caucasians

Apolipoprotein B (apoB) signal peptide (sp) polymorphism was characterized by polymerase chain reaction in blood samples of 58 coronary artery disease (CAD) patients and 319 control individuals of Chinese Han ethnic origin in Taiwan. In the CAD group, 77% of the observed alleles were sp27 (sp with 27 amino acids), and the remaining 23%sp24 (sp with 24 amino acids). The frequency distributions of the apoB sp allele in the control group were 0.81 for sp27 and 0.19 for sp24. The genotype distributions were 0.64 sp27/27, 0.26 sp27/24 and 0.10 sp24/24 in the CAD group; 0.64 sp27/27. 0.33 sp27/24 and 0.03 sp24/24 in the control group. The frequency of sp24/24 was significantly higher (p= 0.012) in the CAD group than in the control group. Several studies have shown that the frequency of sp24/24 is higher in hyperlipidemic than in normolipidemic groups. This marker is probably in linkage disequlibrium with some other atherogenic genes. Our study shows that the differences in both apoB signal peptide alleles and sp27/27 and sp27/24 genotype distributions are statistically significant between the Taiwanese and Caucasians.

Complications of Inoue balloon mitral commissurotomy: Impact of operator experience and evolving technique

BACKGROUND There have been no single-center studies that have systematically addressed the acute outcome of Inoue balloon mitral commissurotomy (BMC) performed in a large series of patients. Accordingly, this study sought to examine the impact of operator experience and continuing technical modifications on the success and complication rates of BMC. METHODS BMC was performed in 799 patients: 469 patients with pliable mitral valves (group 1) and 330 patients with calcified valves and/or severe subvalvular disease (group 2). Acute complications were examined and compared between groups before and after modifications in BMC techniques. Major modifications included the use of a height-derived balloon sizing method for the selection of an appropriate balloon catheter, a cautionary stepwise dilation technique, and avoidance of traction on the interatrial septum during balloon inflations. RESULTS Technical failures were encountered in 4 (0.5%) patients in our early experience. One patient sustained cardiac perforation and tamponade and was the only case requiring emergency surgery. There were no deaths. Systemic embolic events were observed in 11 (1.4%), all among the first 353 patients before the routine use of pre-BMC transesophageal echocardiography. Severe postprocedure angiographic (>/=3+) mitral regurgitation occurred in 4% of patients, 2% in group 1 versus 9% in group 2 (P =.0001). With increased operator experience and technical modifications, this complication was significantly reduced from 5% (7 of 150 patients) to 0% in the last 316 patients in group 1 (P =.0001) and from 11% (26 of 228 patients) to 3% (3 of 101 patients) in group 2 (P =.031). The incidence of significant interatrial shunting (pulmonary-to-systemic flow ratio >/=1.3) was also significantly reduced from 12% to 6% (P =.0034). CONCLUSION Incremental operator experience and ongoing technical refinements in BMC techniques have resulted in a 100% technical success rate and a significant diminution in complications in patients with a wide spectrum of stenotic mitral valve morphologic features.

Pulmonary pseudosequestration receiving arterial supply from a coronary artery fistula : A case report

A forty-eight-year-old man with a history of pulmonary tuberculosis and scarring of both hila and upper lobes was noted to have bilateral pulmonary pseudosequestration, in which the blood supply originated from a coronary artery fistulous vessel arising from the left circumflex artery and draining into the pulmonary artery. This is the first reported patient with the source of blood supply to the pulmonary pseudosequestration arising from a coronary artery fistula.

Analysis of left atrial volume change rate during left ventricular diastolic phase with M-mode echocardiography for differentiation between normal and pseudonormal mitral inflow

Pseudonormalization of mitral inflow is a diagnostic problem in clinical practice. An excellent correlation exists between the change in the left atrial (LA) angiographic area and posterior aortic wall motion. Therefore, we sought to define the role of LA wall motion, indicating LA volume change rate, in patients with normal and pseudonormal mitral inflow. We performed echocardiography after cardiac catheterization in 62 patients with a velocity ratio of early-to-late mitral inflow (E/A ratio) >1. Study patients were classified into 2 groups according to the response of mitral inflow to phase II of the Valsalva maneuver: patients with E/A >1 after the Valsalva maneuver (n = 31, control group), and patients with <1 after the Valsalva maneuver (n = 31, pseudonormal group). The slopes (slope E and A) of early diastolic and late diastolic motion of the LA wall were derived from M-mode analysis together with the time constant of left ventricular (LV) isovolumic relaxation from cardiac catheterization. The values of slope E (41 plus minus 11 vs 61 plus minus 12 mm/s, p <0.001) and slope E/A (0.69 plus minus 0.13 vs 1.32 plus minus 0.35, p <0.001) were significantly lower in the pseudonormal group and were inversely correlated with the time constant of LV isovolumic relaxation (r = 0.64, p <0.001 and r = 0.73, p <0.001, respectively). Using slope E/A <1 as an indicator of relaxation abnormality, the sensitivity, specificity, positive predictive value, and negative predictive value for the detection of pseudonormalization were 94%, 100%, 100%, and 94%, respectively. The slope of LA wall motion, indicating LA volume change rate, during the LV diastolic phase is useful for evaluating pseudonormal LV diastolic dysfunction in the selected patient population.

Late coronary artery stenting in patients with acute myocardial infarction

BACKGROUND The safety and efficacy of late coronary artery stenting of the infarct-related artery after acute infarction has not been evaluated previously. METHODS AND RESULTS Coronary artery stenting was performed in 117 consecutive patients with acute infarction who were receiving ticlopidine/aspirin regimen without coumarin. There were 97 men and 18 women, aged 58+/-11 (mean +/- SD) years. A total of 136 Palmaz-Schatz stents were successfully implanted in 130 lesions 15+/-8 days after acute myocardial infarction (median 9 days) in 115 of 117 (98%) patients. The minimal luminal diameter (MLD) increased from 0.66+/-0.46 to 3.14+/-0.53 mm (P< .001), with an acute gain of 2.49+/-0.61 mm. One patient had acute thrombosis requiring further stenting and another patient received emergency bypass surgery. There was no subacute thrombosis or other complications. During a follow-up duration of 14+/-3 months, 2 patients had angina pectoris develop and 1 died suddenly. Sixty-two patients underwent a follow-up coronary angiography 195+/-36 days after stenting. Restenosis was noted in 8 patients (13%); the MLD was 2.19+/-0.73 mm, the late loss was 0.96+/-0.65 mm (P< .001), the loss index was 0.39+/-0.28, and the net gain was 1.56+/-0.79 mm (P< .001). The angiographic left ventricular ejection fraction increased from 47%+/-12% to 55%+/-12% (P< .001). CONCLUSIONS Late coronary stenting of the infarct-related artery in patients with acute myocardial infarction is a safe and effective late reperfusion therapy and may be beneficial to the patients.

String-plucking as a mechanism of chordal rupture during balloon mitral valvuloplasty using Inoue balloon catheter

Percutaneous transvenous mitral commissurotomy using the Inoue technique was performed in a 59‐year‐old female with mitral stenosis and a severely calcified mitral leaflets. Although not entrapped in the subvalvular apparatus, the balloon catheter was deviated away from the mitral orifice‐apex axis of the left ventricle during the inflation of the proximal balloon, which plucked and severed the chordae tendineae of the posterior mitral leaflet and resulted in severe mitral regurgitation. Cathet. Cardiovasc. Intervent. 47:213–217, 1999.

Comparison of cardiovascular outcomes and all-cause mortality in patients with chronic hepatitis B and C: A 13-year nationwide population-based study in Asia

BACKGROUND AND AIMS Viral hepatitis infection has been linked to increased atherosclerosis. We therefore investigated cardiovascular outcomes in patients with hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. METHODS Electronic medical records during 2000-2012 were retrieved from the Taiwan National Health Insurance Research Database. Exclusion criteria were age <18, history of coexisting HBV and HCV infection, acute coronary syndrome, coronary intervention, venous thromboembolism, peripheral artery disease, stroke, major or gastrointestinal bleeding, malignancy, and a follow-up period <180 days. Patients with HBV and HCV infection were propensity-matched then compared for outcomes. Primary outcomes were cardiovascular events at the 1-year follow-up, 3-year follow-up, 5-year follow-up, and at the end of follow-up. RESULTS 41,554 patients with diagnosis of HBV or HCV were retrieved from 2000 to 2012. After exclusion criteria, 31,943 patients were eligible for analysis and propensity score matched. The study population consisted of 6030 patients with HBV infection and 6030 patients with HCV infection. Risk of composite arterial events (acute coronary syndrome, peripheral artery disease, and acute ischemic stroke) was significantly higher in patients with HCV infection compared with patients with HBV infection (p = 0.012 at 5-year follow-up and p = 0.003 at the end of follow-up). All-cause mortality was significantly higher in patients with HCV infection compared with patients with HBV infection (p < 0.001 at 3-year follow-up, 5-year follow-up, and at the end of follow-up). CONCLUSIONS In patients with chronic viral hepatitis, subjects with HCV infection had a significantly higher risk of composite arterial events and all-cause mortality compared with those with HBV infection.

Clinical outcomes of peripartum cardiomyopathy: a 15-year nationwide population-based study in Asia

Abstract Peripartum cardiomyopathy (PPCM) is the development of heart failure during late pregnancy to months postpartum with potential fatal outcome. However, the disease is not well-studied in Asia. We aimed to investigate the epidemiology and clinical outcomes of PPCM in Taiwan. Electronic medical records were retrieved from Taiwan National Health Insurance Research Database from 1997 to 2011. Patients with PPCM were separated into 3 groups based on the timing of diagnosis. Early: PPCM diagnosed first to ninth month of pregnancy. Traditional: PPCM diagnosed last month of pregnancy till fifth month post-delivery. Late: PPCM diagnosed sixth to twelfth month post-delivery. Primary outcomes defined as cardiac death, all-cause mortality, and major adverse cardiovascular events (MACE) within 1 year. A total of 3,506,081 deliveries during 1997 to 2011 were retrieved and 925 patients with PPCM were identified. Overall incidence of PPCM was 1:3,790 during the 15 years. Early, Traditional, and Late group each had 88, 742, and 95 patients. Cardiac death occurred in 31 patients, all-cause mortality in 72 patients, and MACE in 65 patients. Late group had 2- to 3-fold event rates in cardiac death, all-cause mortality, and MACE compared with Early and Traditional groups. Cumulative incidence showed significant differences for cardiac death (P = .0011), all-cause mortality (P = .0031), and MACE (P = .0014) among 3 groups. Multivariate Cox model showed Late group had significantly worse outcomes after adjusted for clinical variables compared with 2 other groups. Our study is the largest national cohort among Asian countries that showed timing of diagnosis of PPCM had different outcomes. Late diagnosis portended significantly increased morbidity and mortality, even after adjusted for clinical variables.