Ho-Tsung Hsin

Retrograde wire-assisted percutaneous transcatheter closure of persistent ductus arteriosus with Amplatzer duct occluder in the elderly: A new application.

Percutaneous transcatheter closure of persistent ductus arteriosus (PDA) has been well established in the pediatric field. For moderate‐ to large‐sized PDA, the newly developed Amplatzer duct occluder had offered a good solution, but it depends on stiff wire and delivery sheath. We reported two elderly patients of PDA with vascular anatomy too difficult to be antegradely approached and were closed by a retrograde technique by an assisting wire from the descending aorta. The wire served as a guide and tracked the delivery system to cross the ductus from the venous side smoothly. This retrograde wire‐assisted technique could be utilized to overcome the PDA of difficult vascular anatomy, which could not be easily fulfilled by conventional antegrade venous approach. Catheter Cardiovasc Interv 2004;61:264–267.

Effects of clopidogrel on mortality, cardiovascular and bleeding outcomes in patients with chronic kidney disease - data from Taiwan acute coronary syndrome full spectrum registry.

Background The efficacy of clopidogrel is inconclusive in the chronic kidney disease (CKD) population with acute coronary syndrome (ACS). Furthermore, CKD patients are prone to bleeding with antiplatelet therapy. We investigated the efficacy and safety of clopidogrel in patients with ACS and CKD. Methods In a Taiwan national-wide registry, 2819 ACS patients were enrolled. CKD is defined as an estimated glomerular filtration rate of less than 60 ml/min per 1.73 m2. The primary endpoints are the combined outcomes of death, non-fatal myocardial infarction and stroke at 12 months. Results Overall 949 (33.7%) patients had CKD and 2660 (94.36%) patients received clopidogrel treatment. CKD is associated with increased risk of the primary endpoint at 12 months (HR 2.39, 95% CI 1.82 to 3.15, p<0.01). Clopidogrel use is associated with reduced risk of the primary endpoint at 12 months (HR 0.42, 95% CI: 0.29–0.60, p<0.01). Cox regression analysis showed that clopidogrel reduced death and primary endpoints for CKD population (HR 0.35, 95% CI: 0.21–0.61 and HR 0.48, 95% CI: 0.30–0.77, respectively, both p<0.01). Patients with clopidogrel(−)/CKD(−), clopidogrel(+)/CKD(+) and clopidogrel(−)/CKD(+) have 2.4, 3.0 and 10.4 fold risk to have primary endpoints compared with those receiving clopidogrel treatment without CKD (all p<0.01). Clopidogrel treatment was not associated with increased in-hospital Thrombolysis In Myocardial Infarction (TIMI) bleeding in CKD population. Conclusion Clopidogrel could decrease mortality and improve cardiovascular outcomes without increasing risk of bleeding in ACS patients with CKD.

Isolated femoral nerve neuropathy after intra-aortic balloon pump treatment

Intra-aortic balloon pump (IABP)-related neuropathy is an infrequent complication, and the development of motor deficits is even rarer in such cases. We report a 37-year-old man with anterior ST-elevation myocardial infarction who received emergent percutaneous coronary intervention and IABP counterpulsation. Weakness and numbness developed after IABP removal despite lack of evidence of ischemia in the involved extremity. Nerve conduction velocity study and electromyogram led to the diagnosis of femoral nerve neuropathy. The neurologic deficits recovered after 6 months of rehabilitation. This case illustrates the importance of bedside neurologic examination of the involved extremity for early detection of possible injury to the femoral nerve in patients after IABP treatment and insertion of larger bore catheter.

Dimethylthiourea normalizes velocity-dependent, but not force-dependent, index of ventricular performance in diabetic rats: role of myosin heavy chain isozyme.

Hydroxyl radicals and hydrogen peroxide are involved in the pathogenesis of systolic dysfunction in diabetic rats, but the precise mechanisms and the effect of antioxidant therapy in diabetic subjects have not been elucidated. We aimed to evaluate the effects of dimethylthiourea (DMTU), a potent hydroxyl radical scavenger, on both force-dependent and velocity-dependent indexes of cardiac contractility in streptozotocin (STZ)-induced early and chronic diabetic rats. Seventy-two hours and 8 wk after STZ (55 mg/kg) injection, diabetic rats were randomized to either DMTU (50 mg x kg(-1) x day(-1) ip) or vehicle treatment for 6 and 12 wk, respectively. All rats were then subjected to invasive hemodynamic studies. Maximal systolic elastance (E(max)) and maximum theoretical flow (Q(max)) were assessed by curve-fitting techniques in terms of the elastance-resistance model. Both normalized E(max) (E(maxn)) and afterload-adjusted Q(max) (Q(maxad)) were depressed in diabetic rats, concomitant with altered myosin heavy chain (MHC) isoform composition and its upstream regulators, such as myocyte enhancer factor-2 (MEF-2) and heart autonomic nervous system and neural crest derivatives (HAND). In chronic diabetic rats, DMTU markedly attenuated the impairment in Q(maxad) and normalized the expression of MEF-2 and eHAND and MHC isoform composition but exerted an insignificant benefit on E(maxn). Regarding preventive treatment, DMTU significantly ameliorated both E(maxn) and Q(maxad) in early diabetic rats. In conclusion, our study shows that DMTU has disparate effects on Q(maxad) and E(maxn) in chronic diabetic rats. The advantage of DMTU in chronic diabetic rats might involve normalization of MEF-2 and eHAND, as well as reversal of MHC isoform switch.

Detection of Asymptomatic Paroxysmal Atrial Fibrillation with the Trans-Telephonic Electrocardiograph System

Paroxysmal atrial fibrillation (PAF) carries an equally high annual stroke rate as chronic atrial fibrillation (AF). Furthermore, the frequency and duration of PAF are thought to be associated with stroke risk. In this pilot study, a trans-telephonic electrocardiograph (TTE) monitoring system was used to detect asymptomatic PAF and to study the relationship between ischemic stroke and the frequency of PAF. Between December 2004 and April 2006, 70 patients enrolled in the TTE monitoring program. Patients either transmitted electrocardiograms (ECGs) daily or upon experiencing cardiac symptoms. Of the 70 patients included, 25 were diagnosed with PAF. In total, 11% (855/7,768) of the recordings were diagnosed as PAF, yet less than 2% of total calls collected and less than 17% of all the calls with PAF were associated with obvious symptoms. Four patients developed five ischemic strokes resulting in a calculated annual stroke rate of 0.56%. Patients with stroke had more episodes of AF (56.5±106.3 versus 6.7±85.9, p=0.685) and symptomatic AF episodes (9.8±17.5 versus 4.9±8.1, p=0.381) than the patients who did not have a stroke, but the differences were not statistically significant because of the low numbers of patients and episodes. Most PAF episodes were asymptomatic, and the TTE system could easily detect these episodes. Furthermore, these four patients tended to have more episodes of PAF and more symptomatic attacks of PAF than patients who did not have a stroke.

P-1 Remodeling of Myocardial Gap Junctions and its Correlation with Cardiac Contractility in Diabetic Rats

not available at time of printing. Poster Sessions 1: Heart Failure/Myocardial Diseases P-1 Remodeling of Myocardial Gap Junctions and its Correlation with Cardiac Contractility in Diabetic Rats Dong-Feng Yeih1, Pen-Chih Liao1, Ho-Tsung Hsin1, Kuo-Chin Chen1, Ai-Hsian Li1, Yung-Zu Tseng2. 1Department of Cardiology, Far-Eastern Memorial Hospital, Taiwan, 2Department of Cardiology, National Taiwan University, Taiwan Introduction: Gap junctions play an essential role in coupling adjacent cardiomyocytes, ensuring organized propagation of action potential and synchronizing beating in cardiomyocytes. However, it remains unclear that temporal remodeling of myocardial gap junctions and its relation to cardiac contractility in diabetic rats. Methods: Male Wistar rats, weighing 250 to 300 grams, were randomized to injection with either vehicle or streptozotocin (50mg, IP). Invasive hemodynamic studies with simultaneous recordings of left ventricular pressure and aortic flow signals were done at 4, 8 and 12 weeks after injection. Maximal systolic elastance (Emax) and maximum theoretical flow (Qmax) were assessed by curve fitting techniques; protein expression of non-phosphorylated Cx43 (P0) and total amount of Cx43 (T) in the left ventricle by western blotting analysis. Results: Emax was significantly lower in diabetic rats than in controls and Emax was significantly depressed with time in diabetic groups. On the other hand, Qmax was preserved and cardiac output was maintained in diabetic rats. Protein expression of total Cx43 was persistently attenuated in diabetic groups, while P0 was enhanced at 8 and 12 weeks after injection. The ratio of P0 to T was significantly increased with time, which correlated well with the declines in Emax in diabetic rats. Conclusions: Temporal remodeling of myocardial gap junctions, with persistently lower total Cx43 and gradually increased non-phosphorylated Cx43 and the ratio of P0 to T, occurred in the evolution of systolic dysfunction in diabetic rats. P-2 Quantification of Left Ventricular Diastolic Dynamics in Normal and Diseased Myocardium by Speckle-Tracking Echocardiography Kaoru Dohi1, Katsuya Onishi2, Takeshi Takamura1, Emiyo Sugiura1, Hiroshi Nakajima1, Kazuhide Ichikawa1, Masaki Tanabe1, Hiroya Tamada1, Masatoshi Miyahara1, Mashio Nakamura1, Masaaki Ito1. 1Department of Cardiology, Mie University Graduate School of Medicine, Japan, 2Department of Molecular and Laboratory Medicine, Mie University Graduate School of Medicine, Japan Background: The present study aimed to quantify left ventricular (LV) diastolic dynamics and to elucidate their relations to systolic properties in normal and diseased myocardium. Methods: 50 patients with hypertensive LV hypertrophy (LVH: EF 61±8%, QRS 96±16ms), 50 patients with dilated cardiomyopathy (DCM: EF 31±10%, QRS 121±32ms), and 50 normal controls (Control: EF 5±6%, QRS 89±9ms) had echo-study with speckle-tracking strain and strain rate imaging. To quantify LV diastolic relaxation and segmental synchrony, global peak relaxation rate (PRR) during early diastole and standard deviation (SD) of the 18 segmental time-to-PRR (TPRR-SD) were calculated from apical 4-, 2-, and long axis views. To elucidate the relations between diastolic and systolic properties, global peak systolic strain (PSS) and SD of the segmental time-to-peak PSS (TPSS-SD) were also evaluated. Results: LV relaxation and diastolic synchrony were significantly impaired in LVH and was more prominent in DCM (PRR: 0.8±0.3* 1/s in LVH, 0.5±0.2*# 1/s in DCM, and 1.2±0.3 1/s in Control, TPRR-SD: 55±16*ms in LVH, 79±35*# ms in DCM, and 42±13ms in Control, *p < 0.05 vs. Control and #p < 0.05 vs. LVH, respectively). There were strong correlations between PSS and PRR, and TPRR-SD and TPSS-SD (r = 0.83 and r = 0.83, p < 0.05, respectively). Conclusion: Speckle-tracking echocardiography quantified LV diastolic dynamics and exhibited the strong relation to systolic properties.