Objectives We hypothesized that reductions in left atrial volume (LAV) with a cardiac resynchronization therapy–defibrillator (CRT-D) would translate into a subsequent reduction in the risk of atrial ...tachyarrhythmias (AT). Background There is limited information regarding the effect of CRT-D on the risk of AT. Methods Percent reduction in LAV at 1 year following CRT-D implantation (pre-specified as low lowest quartile: <20% reduction in LAV and high ≥20% reduction in LAV response to CRT-D) were related to the risk of subsequent AT (comprising atrial fibrillation, atrial flutter, atrial tachycardia, and supraventricular tachyarrhythmias) among patients enrolled in MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy). Results The cumulative probability of AT 2.5 years after assessment of echocardiographic response was lowest among high LAV responders to CRT-D (3%) and significantly higher among both low LAV responders to CRT-D (9%) and implantable cardioverter-defibrillator–only patients (7%; p = 0.03 for the difference among the 3 groups). Consistently, multivariate analysis showed that high LAV responders to CRT-D experienced a significant 53% (p = 0.01) reduction in the risk of subsequent AT as compared with implantable cardioverter-defibrillator–only patients, whereas low LAV responders did not derive a significant risk reduction with CRT-D therapy (hazard ratio HR: 1.05 95% confidence interval (CI): 0.54 to 2.00; p = 0.89). Patients who developed in-trial AT experienced significant increases in the risk for both the combined endpoint of heart failure or death (HR: 2.28 95% CI: 1.45 to 3.59; p < 0.001) and the separate occurrence of all-cause mortality (HR: 1.89 95% CI: 1.08 to 3.62; p = 0.01). Conclusions In the MADIT-CRT study, favorable reverse remodeling of the left atrium with CRT-D therapy was associated with a significant reduction in risk of subsequent AT. (Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy MADIT-CRT; NCT00180271 )
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
BACKGROUND—Chronic kidney disease (CKD) is strongly related to outcome in cardiovascular diseases. The relationship between treatment of mitral regurgitation (MR) and renal function is not well ...described. We sought to evaluate renal function before and after mitral valve repair by the MitraClip device.
METHODS AND RESULTS—Patients with moderate-to-severe or severe (3+ or 4+, respectively) MR by core laboratory determination who underwent transcatheter mitral valve repair with the MitraClip device in multicenter, investigational trials were included in this study. Estimated glomerular filtration rate (eGFR) was evaluated before and at hospital discharge, 30 days, 6 months, and 1 year after mitral valve repair. Eight hundred fifty-four patients with baseline mean eGFR 61.5±23.1 mL/min/1.73 m were studied, including 438 (51.3%) with eGFR ≥60 mL/min/1.73 m (CKD stage 1 or 2), 371 (42.6%) with eGFR 30 to 59 mL/min/1.73 m (CKD stage 3), and 52 (6.1%) with eGFR <30 mL/min/1.73 m (CKD stage 4 or 5). Baseline renal dysfunction was more prevalent in older patients with a history of heart failure, coronary artery disease, cerebrovascular disease, diabetes mellitus, hypertension, and atrial fibrillation. Baseline eGFR was associated with 1-year survival (P<0.001) after MitraClip repair. At 1-year follow-up, the mean change in eGFR for the overall cohort was −1.0±15.1 mL/min/1.73 m; for patients with CKD stage 1 or 2, stage 3, or stage 4 or 5, mean change was −4.1±16.6, +2.6±12.4, and +4.8±9.5 mL/min/1.73 m, respectively. Linear mixed effect modeling demonstrated a strong association between MR and eGFR, and a statistically significant improvement in eGFR in patients with CKD stage 4 or 5 associated with MR reduction to ≤2+ (P=0.007).
CONCLUSIONS—Renal dysfunction is associated with lower survival in patients with severe MR even after percutaneous mitral valve repair. Reduction in MR severity by the MitraClip device is associated with improvement in renal function at 1 year in patients with baseline renal dysfunction.
CLINICAL TRIAL REGISTRATION—URLhttp://www.clinicaltrials.gov. Unique identifiersNCT00209274, NCT01931956, NCT01940120.
Subarachnoid hemorrhage (SAH) frequently results in myocardial necrosis with release of cardiac enzymes. Historically, this necrosis has been attributed to coronary artery disease, coronary ...vasospasm, or oxygen supply-demand mismatch. Experimental evidence, however, indicates that excessive release of norepinephrine from the myocardial sympathetic nerves is the most likely cause. We hypothesized that myocardial necrosis after SAH is a neurally mediated process that is dependent on the severity of neurological injury.
Consecutive patients admitted with SAH were enrolled prospectively. Predictor variables reflecting demographic (age, sex, body surface area), hemodynamic (heart rate, systolic blood pressure), treatment (phenylephrine dose), and neurological (Hunt-Hess score) factors were recorded. Serial cardiac troponin I measurements and echocardiography were performed on days 1, 3, and 6 after enrollment. Troponin level was treated as a dichotomous outcome variable. We performed univariate and multivariate analyses on the relationships between the predictor variables and troponin level.
The study included 223 patients with an average age of 54 years. Twenty percent of the subjects had troponin I levels >1.0 microg/L (range, 0.3 to 50 microg/L). By multivariate logistic regression, a Hunt-Hess score >2, female sex, larger body surface area and left ventricular mass, lower systolic blood pressure, and higher heart rate and phenylephrine dose were independent predictors of troponin elevation.
The degree of neurological injury as measured by the Hunt-Hess grade is a strong, independent predictor of myocardial necrosis after SAH. This finding supports the hypothesis that cardiac injury after SAH is a neurally mediated process.
Objectives The purpose of this study was to characterize patients with mitral regurgitation (MR) and atrial fibrillation (AF) treated percutaneously using the MitraClip device (Abbott Vascular, ...Abbott Park, Illinois) and compare the results with surgery in this population. Background The EVEREST II (Endovascular Valve Edge-to-Edge Repair Study) randomized controlled trial compared a less invasive catheter-based treatment for MR with surgery, providing an opportunity to assess the impact of AF on the outcomes of both the MitraClip procedure and surgical repair. Methods The study population included 264 patients with moderately severe or severe MR assessed by an independent echocardiographic core laboratory. Comparison of safety and effectiveness study endpoints at 30 days and 1 year were made using both intention-to-treat and per-protocol (cohort of patients with MR ≤2+ at discharge) analyses. Results Pre-existing AF was present in 27% of patients. These patients were older, had more advanced disease, and were more likely to have a functional etiology. Similar reduction of MR to ≤2+ before discharge was achieved in patients with AF (83%) and in patients without AF (75%, p = 0.3). Freedom from death, mitral valve surgery for valve dysfunction, and MR >2+ was similar at 12 months for AF patients (64%) and for no-AF patients (61%, p = 0.3). At 12 months, MR reduction to <2+ was greater with surgery than with MitraClip, but there was no interaction between rhythm and MR reduction, and no difference in all-cause mortality between patients with and patients without AF. Conclusions Atrial fibrillation is associated with more advanced valvular disease and noncardiac comorbidities. However, acute procedural success, safety, and 1-year efficacy with MitraClip therapy is similar for patients with AF and without AF.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background MitraClip is an approved therapy for mitral regurgitation (MR); however, health care resource utilization pre- and post-MitraClip remains understudied. Methods Patients with functional and ...degenerative MR at high surgical risk in the EVEREST II High-Risk Registry and REALISM Continued-Access Study were linked to Medicare data. Pre- and post-MitraClip all-cause death, stroke, myocardial infarction, heart failure (HF), and bleeding hospitalizations were identified. Inpatient costs, adjusted to 2010 US dollars, were calculated, and event rate ratios and cost ratios were estimated with multivariable modeling. Results Among 403 linked patients, the mean age was 80 years, 60% were male, mean baseline left ventricular ejection fraction was 49.6%, 83.3% were New York Heart Association class III/IV, 78.2% were MR grade 3+/4+, and 63.3% had functional MR. All-cause hospitalization decreased from 1,854 to 1,435/1,000 person-years ( P < .001). HF hospitalization decreased following MitraClip (749 vs 332/1000 person-years, P < .001), but bleeding increased (199 vs 298/1000 person-years, P < .001). Changes in stroke and myocardial infarction were not statistically significant. Overall mean Medicare costs per patient were similar pre- and post-MitraClip, although there was a significant decrease in mean costs among those that survived a full year after MitraClip ($18,131 SD $25,130 vs $11,679 SD $22,486, P = .02). Conclusions MitraClip was associated with a reduced rate of all-cause and HF hospitalizations and an increased rate of bleeding hospitalizations. One-year Medicare costs were reduced in those who survived a full year after the MitraClip procedure. Payors and providers seeking to reduce HF hospitalizations and associated Medicare costs may consider MitraClip among appropriate patients likely to survive 1 year.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Left ventricular (LV) systolic dysfunction has been reported in humans with subarachnoid hemorrhage (SAH), and its underlying pathophysiology remains controversial. Possible mechanisms include ...myocardial ischemia versus excessive catecholamine release from sympathetic nerve terminals.
For 38 months, echocardiography and myocardial scintigraphy with technetium sestamibi (MIBI) and meta-(123)Iiodobenzylguanidine (MIBG) were performed on 42 patients admitted with SAH to assess myocardial perfusion and sympathetic innervation, respectively. A blinded observer interpreted the scintigraphic images. Cardiac troponin I (cTI) was measured to quantify the degree of myocyte necrosis. Blinded observers calculated the LV ejection fraction and graded each LV segment as normal (score=1), hypokinetic (score=2), or akinetic (score=3). A wall-motion score was calculated by averaging the sum of the 16 segments. All subjects with interpretable scans (N=41) had normal MIBI uptake. Twelve subjects had either global (n=9) or regional (n=3) absence of MIBG uptake. In comparison with patients with normal MIBG uptake, those with evidence of functional denervation were more likely to have LV regional wall-motion abnormalities (92% versus 52%, P=0.030) and cTI levels >1 microg/L (58% versus 21%, P=0.029).
LV systolic dysfunction in humans with SAH is associated with normal myocardial perfusion and abnormal sympathetic innervation. These findings may be explained by excessive release of norepinephrine from myocardial sympathetic nerves, which could damage both myocytes and nerve terminals.
To evaluate the effect of MRI blood pool contrast agent on 4D flow image quality and ventricular volume measurements. Adult patients referred for clinical cardiac MRI (n = 22) were imaged with 4D ...flow. Patients with renal failure (n = 10) received ferumoxytol, and the remainder (n = 12) received gadofosveset trisodium. Image quality was assessed with (1) signal-to-noise ratio (SNR); (2) contrast-to-noise ratio (CNR); and (3) 5-point Likert scale based on endocardial border definition (1 = none; 2 = partial but unable to visualize; 3 = able to roughly estimate; 4 = visible for most of the cardiac cycle; 5 = excellent definition). A subset (n = 15) had short axis steady-state free precession (SSFP) cine imaging allowing for comparison of standard volumetric measurement technique with 4D flow derived volumetric measurements. 4D flow studies using ferumoxytol demonstrated a higher median Likert score of 5 (IQR, 5–5) versus 3 (IQR, 2–3). Median cavity SNR and CNR were higher for ferumoxytol compared to gadofosveset trisodium 65 (IQR, 50–74) versus 22 (IQR, 14–28), p < 0.001; and 40 (IQR, 32–49) versus 4 (IQR, 3–10), p < 0.001. Good correlation (p < 0.001) was seen between SSFP and 4D flow measured ventricular volumes (ESV and EDV) with ferumoxytol (r = 0.998, mean difference = 1.2 mL, LOA = − 7.7–10.1 mL) and gadofosveset trisodium (r = 0.942, mean difference = − 2.7 mL, LOA = − 35.7–27.1 mL). Ferumoxytol used off-label as an MRI blood pool contrast agent offers an attractive alternative to gadofosveset trisodium in patients with renal failure, with excellent 4D flow image quality and good correlation of volumetric measurements compared to the CMR reference (SSFP).
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Long-term ventricular resynchronization therapy improves symptom status. Changes in left ventricular remodeling have not been adequately evaluated.
Fifty-three patients with systolic heart failure ...and bundle-branch block underwent implantation of biventricular stimulation (BVS) devices as part of a randomized trial. Echocardiograms were acquired at randomization and at 6-week intervals until completion of 12 weeks of continuous BVS. There were no changes in heart rate or QRS duration after 12 weeks of BVS. Serum norepinephrine values did not change with BVS. After 12 weeks of BVS, left atrial volume decreased. Left ventricular end-systolic and end-diastolic dimensions and left ventricular end-systolic volume also decreased after 12 weeks of BVS. Sphericity index did not change. Measures of systolic function, including left ventricular outflow tract and aortic velocity time integral and myocardial performance index, improved.
Long-term resynchronization therapy results in atrial and ventricular reverse remodeling and improved hemodynamics.
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