Percutaneous Intramyocardial Septal Radiofrequency Ablation for Interventricular Septal Reduction: An Ovine Model with 1-Year Outcomes.
经皮心肌间隔射频消融治疗室间隔缩小术: 1 年结局的绵羊模型。
- 作者列表："Liu F","Fu J","Hsi D","Sun C","He G","Hu R","Zhang J","Liu L
BACKGROUND:Percutaneous intramyocardial (PIM) septal radiofrequency ablation (SRA) is a novel treatment approach for hypertrophic obstructive cardiomyopathy patients, but there has been lack of a large animal model to study PIM-SRA. We aimed to validate the long-term safety and efficacy of PIM-SRA and to observe pathological changes of the ablated interventricular septum (IVS) in a healthy sheep model. METHODS AND RESULTS:Twelve sheep were randomized to the PIM-SRA group (n = 6) and the sham group (n = 6). In the PIM-SRA group, a radiofrequency (RF) electrode was inserted into the IVS with a maximum power of 80 W for 5 min. In the sham group, the RF electrode tip was positioned in the IVS segment but without RF power delivery. Septal hypokinesis was seen in all PIM-SRA group animals immediately after the procedure; the systolic wall thickening rate and motion amplitude of the ablated region decreased (p < 0.01), and the diastolic IVS thickness also decreased significantly over time (p < 0.01). ECG showed that all the sheep had normal sinus rhythm during the follow-up. Pathological examinations revealed scar tissue in the ablated region as expected. CONCLUSIONS:PIM-SRA produced precisely ablated myocardial tissue, reduced the IVS thickness significantly, preserved the global LV function, and avoided the incidence of conduction system damage in the long term. PIM-SRA was found to be a safe and effective minimally invasive septal reduction therapy.
背景: 经皮心肌内 (PIM) 间隔射频消融术 (SRA) 是肥厚型梗阻性心肌病患者的一种新型治疗方法，但目前尚缺乏大型动物模型来研究 PIM-SRA。我们旨在验证 PIM-SRA 的长期安全性和有效性，并观察健康绵羊模型中消融的室间隔 (IVS) 的病理变化。 方法和结果: 12 只绵羊随机分为 PIM-SRA 组 (n = 6) 和假手术组 (n = 6)。在 PIM-SRA 组中，在 IVS 中插入射频 (RF) 电极，最大功率为 80 W，持续 5 min。在假手术组中，射频电极尖端位于 IVS 段，但无射频功率输送。所有 PIM-SRA 组动物术后即刻均出现室间隔运动减退; 消融区收缩期室壁增厚率和运动幅度降低 (p
METHODS:Abstract Background Ischemic cardiomyopathy is a high-cost, resource-intensive public health burden that is associated with a 1-year mortality rate of about 16% in western population. Different in patient ethnicity and pattern of practice may impact the clinical outcome. We aim to determine 1-year mortality and to identify factors that significantly predicts 1-year mortality of Thai patients with ischemic cardiomyopathy. Methods This prospective multicenter registry enrolled consecutive Thai patients that were diagnosed with ischemic cardiomyopathy at 9 institutions located across Thailand. Patients with left ventricular function 75% in the left main or proximal left anterior descending artery or coronary angiography, and/or two major epicardial coronary stenoses; 2) prior myocardial infarction; 3) prior revascularization by coronary artery bypass graft or percutaneous coronary intervention; or, 4) magnetic resonance imaging pattern compatible with ischemic cardiomyopathy. Baseline clinical characteristics, coronary and echocardiographic data were recorded. The 1-year clinical outcome was pre-specified. Results Four hundred and nineteen patients were enrolled. Thirty-nine patients (9.9%) had died at 1 year, with 27 experiencing cardiovascular death, and 12 experiencing non-cardiovascular death. A comparison between patients who were alive and patients who were dead at 1 year revealed lower baseline left ventricular ejection fraction (LVEF) (26.7 ± 7.6% vs 30.2 ± 7.8%; p = 0.021), higher left ventricular end-diastolic volume (LVEDV) (185.8 ± 73.2 ml vs 155.6 ± 64.2 ml; p = 0.014), shorter mitral valve deceleration time (142.9 ± 57.5 ml vs 182.4 ± 85.7 ml; p = 0.041), and lower use of statins (94.7% vs 99.7%; p = 0.029) among deceased patients. Patients receiving guideline-recommended β-blockers had lower mortality than patients receiving non-guideline-recommended β-blockers (8.1% vs 18.2%; p = 0.05). Conclusions The results of this study revealed a 9.9% 1-year mortality rate among Thai ischemic cardiomyopathy patients. Doppler echocardiographic parameters significantly associated with 1-year mortality were LVEF, LVEDV, mitral E velocity, and mitral valve deceleration time. The use of non-guideline-recommended β-blockers rather than guideline recommended β-blockers were associated with increased with 1-year mortality. Guidelines recommended β-blockers should be preferred. Trial registration Thai Clinical Trials Registry TCTR20190722002. Registered 22 July 2019. “Retrospectively registered”.
METHODS:Abstract Background Peripartum cardiomyopathy (PPCM) is rare and potentially life-threatening; its etiology remains unclear. Imaging characteristics on cardiovascular magnetic resonance (CMR) and their prognostic significance have rarely been studied. We sought to determine CMR’s prognostic value in PPCM by using T1 and T2 mapping techniques. Methods Data from 21 PPCM patients from our CMR registry database were analyzed. The control group comprised 20 healthy age-matched females. All subjects underwent comprehensive contrast-enhanced CMR. T1 and T2 mapping using modified Look-Locker inversion recovery and T2 prep balanced steady-state free precession sequences, respectively. Ventricular size and function, late gadolinium enhancement (LGE), myocardial T1 value, extracellular volume (ECV), and T2 value were analyzed. Transthoracic echocardiography was performed at baseline and during follow-up. The recovered left ventricular ejection fraction (LVEF) was defined as LVEF ≥50% on echocardiography follow-up after at least 6 months of the diagnosis. Results CMR imaging showed that the PPCM patients had severely impaired LVEF and right ventricular ejection fraction (LVEF: 26.8 ± 10.6%; RVEF: 33.9 ± 14.6%). LGE was seen in eight (38.1%) cases. PPCM patients had significantly higher native T1 and ECV (1345 ± 79 vs. 1212 ± 32 ms, P < 0.001; 33.9 ± 5.2% vs. 27.1 ± 3.1%, P < 0.001; respectively) and higher myocardial T2 value (42.3 ± 3.7 vs. 36.8 ± 2.3 ms, P < 0.001) than did the normal controls. After a median 2.5-year follow-up (range: 8 months-5 years), six patients required readmission for heart failure, two died, and 10 showed left ventricular function recovery. The LVEF-recovered group showed significantly lower ECV (30.7 ± 2.1% vs. 36.8 ± 5.6%, P = 0.005) and T2 (40.6 ± 3.0 vs. 43.9 ± 3.7 ms, P = 0.040) than the unrecovered group. Multivariable logistic regression analysis showed ECV (OR = 0.58 for per 1% increase, P = 0.032) was independently associated with left ventricular recovery in PPCM. Conclusions Compared to normal controls, PPCM patients showed significantly higher native T1, ECV, and T2. Native T1, ECV, and T2 were associated with LVEF recovery in PPCM. Furthermore, ECV could independently predict left ventricular function recovery in PPCM.
METHODS:BACKGROUND:Atrial fibrillation (AF) is the most common arrhythmia in hypertrophic cardiomyopathy (HCM) and is associated with adverse outcomes in HCM patients. Although the left atrial (LA) diameter has consistently been identified as a strong predictor of AF in HCM patients, the relationship between LA dysfunction and AF still remains unclear. The aim of this study is to evaluate the LA function in patients with non-obstructive HCM (NOHCM) utilizing cardiovascular magnetic resonance feature tracking (CMR-FT).,METHODS:Thirty-three patients with NOHCM and 28 healthy controls were studied. The global and regional LA function and left ventricular (LV) function were compared between the two groups. The following LA global functional parameters were quantitively analyzed: reservoir function (total ejection fraction [LA total EF], total strain [ε], peak positive strain rate [SRs]), conduit function (passive ejection fraction [LA passive EF], passive strain [ε], peak early-negative SR [SRe]), and booster pump function (active ejection fraction [LA active EF], active strain [ε], peak late-negative SR [SRa]). The LA wall was automatically divided into 6 segments: anterior, antero-roof, inferior, septal, septal-roof and lateral. Three LA strain parameters (ε, ε, ε) and their corresponding strain rate parameters (SRs, SRe, SRa) during the reservoir, conduit and booster pump LA phases were segmentally measured and analyzed.,RESULTS:The LA reservoir (LA total EF: 57.6 ± 8.2% vs. 63.9 ± 6.4%, p < 0.01; ε: 35.0 ± 12.0% vs. 41.5 ± 11.2%, p = 0.03; SRs: 1.3 ± 0.4 s vs. 1.5 ± 0.4 s, p = 0.02) and conduit function (LA passive EF: 28.7 ± 9.1% vs. 37.1 ± 10.0%, p < 0.01; ε: 18.7 ± 7.9% vs. 25.9 ± 10.0%, p < 0.01; SRe: - 0.8 ± 0.3 s vs. -1.1 ± 0.4 s, p < 0.01) were all impaired in patients with NOHCM when compared with healthy controls, while LA booster pump function was preserved. The LA segmental strain and strain rate analysis demonstrated that the ε, ε, SRe of inferior, SRs, SRe of septal-roof, and SRa of antero-roof walls (all p < 0.05) were all decreased in the NOHCM cohort. Correlations between LA functional parameters and LV conventional function and LA functional parameters and baseline parameters (age, body surface area and NYHA classification) were weak. The two strongest relations were between ε and LA total EF(r = 0.84, p < 0.01), ε and LA active EF (r = 0.83, p < 0.01).,CONCLUSIONS:Compared with healthy controls, patients with NOHCM have LA reservoir and conduit dysfunction, and regional LA deformation before LA enlargement. CMR-FT identifies LA dysfunction and deformation at an early stage.