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ABSTRACT: In doxorubicin-induced cardiomyopathy (DIC), the sequence of decrease in multidirectional myocardial deformation has not been clearly elucidated.
We investigated the sequence of myocardial deformations in rat DIC, using two-dimensional speckle tracking echocardiography (2DSTE).
Twenty rats were treated with doxorubicin (1.25 mg/kg × 16 times, intraperitoneal) for 4 weeks and compared with nine control rats. Myocardial strain analysis with 2DSTE, as well as conventional echocardiography, was obtained.
Compared with baseline, longitudinal strain/strain rate (LS/LSr) decreased at week 2 (-15.7 ± 1.5 to -14.1 ± 1.4%, P = 0.01 for LS; -4.4 ± 0.7 to -3.9 ± 0.5 per second, P = 0.009 for LSr). Left ventricular ejection fraction (LVEF) and circumferential strain (CS) decreased at week 4 (80.3 ± 3.2 to 78.1 ± 3.3%, P = 0.031 for LVEF; -18.6 ± 1.9 to -15.0 ± 3.4%, P = 0.019 for CS). Circumferential strain rate (CSr) decreased at week 6 (-5.5 ± 0.8 to -4.6 ± 1.0 per second, P = 0.008). Radial strain/strain rate (RS/RSr) decreased at week 8 (54.8 ± 9.4 to 43.7 ± 10.6%, P = 0.005 for RS; 8.0 ± 1.1 to 7.0 ± 1.1 per second, P = 0.005 for RSr), while there was no significant change in LS/LSr, LVEF, CS/CSr, or RS/RSr in the control group. LVEF had the highest correlation with LS (r =-0.607, P = 0.000) and the lowest correlation with RSr (r = 0.357, P = 0.000).
In DIC of rat hearts, LS/LSr decreased first, and then LVEF, CS, CSr, RS/RSr subsequently decreased. LS/LSr is considered to be a more sensitive predictor than LVEF in progressive rat DIC, and RS/RSr was preserved until the last stage.
Echocardiography 04/2012; 29(6):720-8. · 1.24 Impact Factor
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ABSTRACT: Doxorubicin is widely used anti-neoplastic drug but has serious cardiotoxicity. Long-term cardioprotective effects of statin and carvedilol against delayed cardiotoxicity of doxorubicin was not well elucidated.
To evaluate long-term cardioprotective effects of co-administered rosuvastatin and carvedilol against chronic doxorubicin-induced cardiomyopathy (DIC) in rats.
Sixty-one rats were assigned to six groups: group I, control; group II, doxorubicin only (1.25 mg/kg, bi-daily, I.P.); group III, doxorubicin + rosuvastatin (2 mg/kg/day, P.O.); group IV, doxorubicin + rosuvastatin(10 mg/kg/day, P.O.); group V, doxorubicin + carvedilol (5 mg/kg/day, P.O.); group VI, doxorubicin + carvedilol (10 mg/kg/day, P.O.). Drugs were administered for 4 weeks (by week 4) and rats were observed without drugs for 4 weeks (by week 8).
After 4 weeks discontinuation of drugs (week 8), group III showed higher +dP/dt (p = 0.058), lower -dP/dt (p = 0.009), lower left ventricular (LV) tissue malondialdehyde (MDA; p = 0.022), and less LV fibrosis (p = 0.011) than group II. Group IV showed similar results to group III. However, in group V and VI, carvedilol failed to reduce LV dysfunction, elevation of troponin or myocardial fibrosis, although group V showed lower LV tissue MDA (p = 0.004) than group II.
Myocardial injury and LV systolic/diastolic dysfunction at week 8 was alleviated by co-administered rosuvastatin, but not by carvedilol. It is unclear whether the cardioprotective effect of rosuvastatin is attributed to a suppression of oxidative stress induced by doxorubicin, because carvedilol did not exhibit a cardioprotective effect despite its antioxidant effects.
Toxicology mechanisms and methods 03/2012; 22(6):488-98. · 1.03 Impact Factor
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ABSTRACT: Spontaneous coronary artery dissection (SCAD) is a rare cause of myocardial ischemia. Multivessel SCAD is much rarer than single vessel involvement and acute coronary syndrome is the most frequent clinical presentation of a patient with SCAD. The patient in this report had SCAD in both the left anterior descending and right coronary arteries at the same time. However, the clinical manifestation was not acute coronary syndrome but rather congestive heart failure. Successful angioplasty and stent placement was performed and the symptoms of congestive heart failure were successfully resolved with medical treatment.
Heart and Vessels 12/2010; 26(3):338-41. · 2.05 Impact Factor
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ABSTRACT: Despite its low incidence, stent thrombosis (ST) is one of the most dreaded complications of percutaneous coronary intervention. Endeavor (Medtronics Europe SA) is a new zotarolimus-eluting stent (ZES) with a favorable safety profile that was reported in early and ongoing trials. However, few lethal stent thromboses related to this new drug eluting stent (DES) have been reported. We experienced a case of simultaneous subacute ZES thromboses, 6 days after stent implantations in the proximal left anterior descending artery and the proximal right coronary artery (RCA).
Korean Circulation Journal 05/2010; 40(5):243-6.
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ABSTRACT: This is a report of Brugada-like ST-segment abnormalities related to acute myocarditis associated with hematologic disorders. Electrocardiographic (ECG) pattern of ST-segment elevation in the right precordial leads mimicking Brugada syndrome may relate to pathological abnormalities due to hematologic disorders that may have genetic, infective, or inflammatory origins. We describe two cases of myocardial involvement of hemotologic disorders, manifested with Brugada-like ECG findings.
Pacing and Clinical Electrophysiology 07/2008; 31(6):761-4. · 1.35 Impact Factor
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ABSTRACT: The aim of this study was to investigate the impact of obstructive sleep apnea (OSA) on left ventricular (LV) functional changes by using tissue Doppler imaging-derived indexes in patients with OSA. We studied 62 patients classified into 3 groups, namely 18 with mild to moderate OSA, 24 with severe OSA, and 20 control subjects without OSA according to the apnea-hypopnea index (AHI) on complete overnight polysomnogram. All underwent conventional and tissue Doppler echocardiographies. Only early diastolic velocity (Ea; -6.2 +/- 0.3 vs -7.1 +/- 0.3 vs -7.3 +/- 0.3 cm/s, respectively, for the 3 groups, p = 0.023) was significantly decreased in the severe OSA group. Other echocardiographic parameters of diastolic function such as isovolumic relaxation time, deceleration time, mitral inflow early/late wave velocity ratio, and pulmonary vein systolic/diastolic pulmonary vein velocity ratio were comparable among the 3 groups. AHI was correlated only with tissue Doppler imaging-derived indexes of LV diastolic function (Ea r = -0.382, p = 0.002; Ea/late diastolic velocity r = -0.329, p = 0.009), but not with conventional Doppler indexes. AHI remained a significant predictor of Ea after adjusting for age, heart rate, fasting glucose level, blood pressure, body mass index, and LV mass index in a multiple stepwise linear regression model (p = 0.007). In conclusion, only patients with severe OSA showed a greater impairment of LV diastolic function. Of all echocardiographic parameters of diastolic dysfunction investigated, only Ea was identified as the best index to demonstrate an association between LV diastolic dysfunction and severity of OSA independently of body mass index, diabetes mellitus, and hypertension.
The American Journal of Cardiology 07/2008; 101(11):1663-8. · 3.37 Impact Factor
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ABSTRACT: A papillary fibroelastoma is rare, but it is the most common primary tumor of the cardiac valves. Most papillary fibroelastomas affect the left-sided heart valves, such as the aortic and mitral valves; however, they also rarely affect the pulmonary valve. Generally, surgical removal is strongly recommended to prevent its potential thromboembolic risks, especially in cases of left-sided cardiac involvement. However, there are few reports on the treatment of asymptomatic, small, right-sided cardiac fibroelastomas. We present a rare case of an asymptomatic papillary fibroelastoma occurring on the pulmonary valve, which was detected by transthoracic echocardiography, transesophageal echocardiography, and a 64-slice cardiac computed tomography scan, and which was surgically removed.
Heart and Vessels 08/2007; 22(4):284-6. · 2.05 Impact Factor
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ABSTRACT: Although amiodarone appears to have few pro-arrhythmic effects, torsade de pointes (TdP) has been observed during long-term drug administration, usually in conjunction with electrolyte disturbances, a change in drug dosage, or concomitant drug therapy. We report two cases of amiodarone-induced TdP shortly after administration of a low dose of oral amiodarone, in the absence of predisposing factors.
Europace 01/2007; 8(12):1051-3. · 1.98 Impact Factor
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ABSTRACT: Increased aortic stiffness measured by pulse wave velocity (PWV) and left ventricular hypertrophy (LVH) are independent risk factors of cardiovascular events in hypertensive patients. We have conducted a prospective study to examine the effects of the angiotensin II receptor antagonist (irbesartan) on PWV and LVH in hypertensive patients.
A total of 52 untreated hypertensive patients (age: 53.3 +/- 8.0 yrs) were enrolled; they had no evidence of associated cardiovascular complications. Blood pressure, heart rate, aortic PWV and left ventricular mass index (LVMI) by 2-D echocardiography were measured at baseline and after irbesartan treatment (150 mg or 300 mg/day) at 12 weeks and 24 weeks.
Blood pressure was significantly decreased after 12 weeks and 24 weeks of treatment compared to baseline (SBP: 134.6 +/- 13.3 mmHg, 134.0 +/- 11.0 mmHg vs 163.7 +/- 13.8 mmHg p < 0.001, DBP: 86.0 +/- 10 mmHg, 83.07 mmHg vs 102.4 +/- 9.6 mmHg p < 0.001, respectively) without significant change in heart rate. LVMI decreased at 12 weeks and at 24 weeks after treatment compared to baseline (from 145.5 +/- 35.1 g/m2 at baseline to 137.5 +/- 35.4 g/m2 at 12 weeks, p = 0.017 and 135.3 +/- 35.4 g/m2 at 24 weeks, p = 0.008). Aortic PWV was decreased after irbesartan treatment at 12 weeks (from 9.6 +/- 2.8 m/sec to 8.7 +/- 3.1 m/sec at 12 weeks, p = 0.064) and at 24 weeks (from 9.6 +/- 2.9 m/sec to 7.7 +/- 2.1 m/sec at 24 weeks, p = 0.007).
Long-term treatment with irbesartan may reduce arterial stiffness and regression of LVH in hypertensive patients. The pleiotropic effects of irbesartan, further decreasing PWV without change of BP between 12 and 24 weeks of treatment, may have favorable vascular effects on arterial stiffness and LVH.
The Korean Journal of Internal Medicine 06/2006; 21(2):103-8.
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ABSTRACT: Action potential duration restitution (APDR) plays a role in initiation and maintenance of ventricular tachycardia (VT)/ventricular fibrillation (VF). We hypothesized that the steeply sloped APDR and its spatial heterogeneity contribute to VT/VF inducibility in patients with ventricular arrhythmia.
After programmed ventricular stimulation (PVS) for evaluation of clinically documented VT, patients (n = 20, 15 male, age 52.5 +/- 9.5 years) were divided into two groups: inducible sustained VT/VF (IVT, n = 10) and noninducible VT/VF (NVT, n = 10). Data were compared with the corresponding results obtained from normal controls (C, n = 10). Right ventricular (RV) monophasic action potential duration at 90% repolarization (APD90) and ventricular effective refractory period (VERP) in the right ventricular apex (RVA) and right ventricular outflow tract (RVOT) were determined. APDR was acquired by scanning diastole with premature ventricular beats during a pacing cycle length of 600 msec (S1-S2) in all patients and by rapid pacing at the cycle lengths that induced APD alternans in three patients. Maximal slopes (Smax) of the APDR curves and DeltaAPD90 (APD90 at S2 400 ms - APD90 at the shortest S2) were measured. VERP and APD90 at each RV site did not differ among the three groups. Smax obtained by S1-S2 (1.6 +/- 0.6) did not differ from Smax obtained by rapid pacing (1.2 +/- 0.7), with a significant correlation noted between these values (r = 0.92, P < 0.01). The IVT group had a higher spatial dispersion of Smax (Smax at RVOT - Smax at RVA) compared to the C group (P < 0.05), with no difference between the NVT group and the IVT or C groups. The IVT group had a higher spatial dispersion of DeltaAPD90 compared to the NVT and C groups (P < 0.01, respectively). Smax at the RVOT (2.7 +/- 1.9) was steeper than that at the RVA (1.9 +/- 1.2, P < 0.05). Inducibility of sustained VT/VF was greater at the RVOT (83.3%) than at the RVA (50.0%, P < 0.05).
In patients with ventricular arrhythmia, VT/VF is highly inducible under conditions of greater spatial dispersion of ventricular refractoriness and APDR.
Journal of Cardiovascular Electrophysiology 01/2005; 15(12):1357-63. · 3.06 Impact Factor
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ABSTRACT: A recent study has shown that triple anti-platelet therapy (cilostazol+clopidogrel+aspirin) resulted in a significantly lower restenosis rate after coronary stenting than did conventional therapy (clopidogrel+aspirin). However, the anti-platelet effects of cilostazol, when combined with clopidogrel and aspirin, have not been evaluated.
Low dose cilostazol (50 mg/BID) was given to 47 patients who had already been taking clopidogrel (75 mg/day) and aspirin (100 mg/day) for more than 1 month subsequent to coronary stenting due to AMI and unstable angina. Markers of platelet activation, P-selectin and activated GPIIb/IIIa on platelets, were measured at baseline and 2 weeks after cilostazol treatment. We empirically divided patients into tertiles (low, n =16; moderate, n = 14; high group, n = 17), according to the baseline P-selectin expression. We then performed a comparative assessment of the anti-platelet effects of cilostazol at baseline and after 2 weeks of cilosatzol administration.
P-selectin was significantly decreased after 2 weeks of cilostazol treatment in total patients (n = 47, 3.2 +/- 2.4% to 2.0 +/- 1.9%, p = 0.03). This inhibition of P-selectin expression was mainly achieved in the moderate and high P-selectin groups (low group; 1.4 +/- 0.5 to 1.9 +/- 1.3%, p > 0.05, moderate group; 2.5 +/- 0.3 to 1.3 +/- 0.3%, p < 0.05, high group; 5.4 +/- 2.7 to 2.7 +/- 2.8%, p < 0.05). Activated GPIIb/IIIa was not significantly changed (13.5% to 17.6%, p > 0.05). Underying disease, cardiovascular risk factors, concomitant medication including statin, and hsCRP were not related to the degree of P-selectin expression.
Our data demonstrated that cilostazol treatment in addition to conventional anti-platelet therapy provides more effective suppression of platelet P-selectin expression in patients with relatively high platelet activity.
The Korean Journal of Internal Medicine 01/2005; 19(4):230-6.
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ABSTRACT: Recent studies have demonstrated that the size and shape of the hyperenhanced areas on contrast-enhanced magnetic resonance imaging (ceMRI) were nearly identical to areas of irreversible injury, as defined by histochemical staining. We compared the transmural extent of infarct (TEI), as defined by ceMRI, to the initial ECG findings for acute myocardial infarction (AMI), and we also assessed functional contractility according to TEI.
12 patients who presented with their first myocardial infarction underwent cine and ceMRI 4 weeks later after their successful revascularization. TEI and wall thickening were determined by using a 30-segment model.
Infarction was observed in 81 (23.9%) segments, of which 46 segments (56.8%) had abnormal wall motion and 35 segments (43.2%) had normal wall motion. Of the 35 segments, 33 (94.3%) had subendocardial infarction. 17 segments had infarct of less than 25% of the wall thickness, and all of them had normal wall motion. On the other hand, 11 segments had infarct of more than 75% of wall thickness, of which 11 (100%) had abnormal wall motion. None of segments with nearly transmural infarction were observed in non ST-elevation AMI. The majority of the segments with infarct had non-transmural infarction (87.5%), even if the segments were in ST-elevation AMI (76.1%). Infarct size, as defined by ceMRI, was strongly correlated with peak CK-MB and Troponin-T (r = 0.96, p < 0.001, r = 0.91, p < 0.001, respectively).
TEI defined by ceMRI is inversely related to the contractility after revascularization in AMI. We were able to predict the future contractile function of segments with infarction using ceMRI before revascularization.
The Korean Journal of Internal Medicine 01/2005; 19(4):213-9.
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ABSTRACT: Arterial stiffness has been known as a major contributory factor to cardiovascular (CV) morbidity and mortality in patients with hypertension. Pulse wave velocity (PWV), a surrogate measurement of large artery damage, has not been ascertained as an independent risk factor of coronary artery disease (CAD). The aim of this study was to assess whether PWV is associated with CV risk.
We prospectively enrolled 326 consecutive patients undergoing coronary angiography for the assessment of suspected CAD. Arterial stiffness was assessed through aorto-femoral PWV using fluid-filled system. PWV was higher in patients with CAD than those without CAD (12.5 +/- 5.1 vs 10.2 +/- 3.1 m/s, p < 0.001). In multivariate logistic regression analysis, after entering for age, diabetes and other CV risk factors, PWV remained the significant independent variable for CAD (p = 0.050). When the severity of CAD was expressed as one-, two- or three-vessel disease, PWV was a significantly associated with the severity of CAD (p < 0.001).
Our findings suggest that PWV is an independent risk marker for CAD, as well as strongly associated with the severity of CAD.
Blood Pressure 02/2004; 13(6):369-75. · 1.43 Impact Factor
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Jeong Cheon Ahn,
Ho Jun Lee,
Sung Hee Shin,
Eun Mi Lee,
Kyo Seung Hwang,
Woo Heuk Song,
Chang Gyu Park,
Young Hoon Kim,
Hong Seog Seo,
Wan Joo Shim,
Dong Joo Oh
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ABSTRACT: Background and Objectives:The state of the coronary microcirculation is one of the major determinants of the prognosis of patients who have had successful reperfusion for acute myocardial infarction (AMI. We in- vestigated whether the vasodilatory reserve in the infarcted myocardium correlated with the perfusion state at early recovery phase in 12 anterior wall AMI patients. Materials and Method:We measured coronary flow variables with Doppler wire, after successful revascularizaiton by PTCA within 2 weeks following AMI and 13±0.5 months later, in the infarct related artery of AMI pts who received successful thrombolytic th- erapy. Myocardial perfuison state was evaluated by semiquantitative method (opacification score and opa- cification index with myocardial contrast echocardiography (MCE at the same time. Patients were divided into two groups according to initial perfusion status (perfusion defect group (PD (+ , n=7, no-perfusion defect group (PD(-, n=5. Results:10 minutes after completion of the intervention, the coronary flow reserve (CFR was 2.0±0.4 (mean±SD;it increased to 2.7±0.7 (p=0.002 at follow up. The difference of initial CFR was not significant between PD (+ and PD (- group. However, it significantly improved in the PD (- group compared to PD (+ group at follow up (3.19±0.39 vs. 2.39±0.7, p=0.046. Opacification index and initial CFR were significantly correlated (r=0.79, p
