Idiopathic Nonischemic Cardiomyopathy Research Articles

Abstract 11589: Total Artificial Heart Placement in a Case of Recurrent Ventricular Tachycardia Storm

Background: Electrical storm is defined as three or more episodes of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) within a 24-hour period requiring termination by cardioversion, anti-tachycardia pacing (ATP) or defibrillation. It can be a particularly challenging syndrome to treat when refractory to standard of care therapies, which include antiarrhythmics, sedation, and ablation. We present a case of refractory electrical storm requiring total artificial heart placement (TAH) as a bridge to transplant. Case: A 65-year-old male with a history of idiopathic non-ischemic cardiomyopathy presented with VF arrest. After return of spontaneous circulation, he was admitted to the cardiac intensive care unit. Implantable cardioverter defibrillator (ICD) interrogation showed 38 shocks delivered over the prior two-week period. Coronary angiography showed no obstructive coronary disease and an intraaortic balloon pump (IABP) was placed for cardiogenic shock. He was intubated and sedated on fentanyl and propofol. He continued to have episodes of VT despite treatment with lidocaine, procainamide, and amiodarone drips. Further trials of paralysis and left stellate ganglion nerve block did not suppress his VT. Since the patient was refractory to all prior interventions, was deemed too unstable for VT ablation, and had a prolonged anticipated wait time for heart transplant, he underwent TAH placement as a bridge to heart transplant. He recovered well and eventually underwent successful heart transplant. Discussion: Management of electrical storm requires a stepwise approach including administration of antiarrhythmics, sedation, mechanical hemodynamic support, and catheter ablation. Our patient had incessant VT despite exhaustive medical and supportive therapies, but was too unstable to undergo VT ablation. In cases of refractory VT storm, definitive treatment with heart transplantation must be considered, but bridging patients to transplant poses a challenge. Our patient underwent TAH placement and was successfully stabilized prior to transplant. In centers with this capability, TAH should be recognized as a legitimate option in the pathway for VT, particularly with a long anticipated wait time for heart transplant.

PATIENTS WITH NON-ISCHEMIC CARDIOMYOPATHY AND MID-WALL STRIAE HAVE SIMILAR OUTCOMES AS PATIENTS WITH ISCHEMIC CARDIOMYOPATHY: A PROPENSITY-MATCHED ANALYSIS

PATIENTS WITH NON-ISCHEMIC CARDIOMYOPATHY AND MID-WALL STRIAE HAVE SIMILAR OUTCOMES AS PATIENTS WITH ISCHEMIC CARDIOMYOPATHY: A PROPENSITY-MATCHED ANALYSIS

Machine Learning Patient-Specific Prediction of Heart Failure Hospitalization Using Cardiac MRI-Based Phenotype and Electronic Health Information.

BackgroundHeart failure (HF) hospitalization is a dominant contributor of morbidity and healthcare expenditures in patients with systolic HF. Cardiovascular magnetic resonance (CMR) imaging is increasingly employed for the evaluation of HF given capacity to provide highly reproducible phenotypic markers of disease. The combined value of CMR phenotypic markers and patient health information to deliver predictions of future HF events has not been explored. We sought to develop and validate a novel risk model for the patient-specific prediction of time to HF hospitalization using routinely reported CMR variables, patient-reported health status, and electronic health information.MethodsStandardized data capture was performed for 1,775 consecutive patients with chronic systolic HF referred for CMR imaging. Patient demographics, symptoms, Health-related Quality of Life, pharmacy, and routinely reported CMR features were provided to both machine learning (ML) and competing risk Fine-Gray-based models (FGM) for the prediction of time to HF hospitalization.ResultsThe mean age was 59 years with a mean LVEF of 36 ± 11%. The population was evenly distributed between ischemic (52%) and idiopathic non-ischemic cardiomyopathy (48%). Over a median follow-up of 2.79 years (IQR: 1.59–4.04) 333 patients (19%) experienced HF related hospitalization. Both ML and competing risk FGM based models achieved robust performance for the prediction of time to HF hospitalization. Respective 90-day, 1 and 2-year AUC values were 0.87, 0.83, and 0.80 for the ML model, and 0.89, 0.84, and 0.80 for the competing risk FGM-based model in a holdout validation cohort. Patients classified as high-risk by the ML model experienced a 34-fold higher occurrence of HF hospitalization at 90 days vs. the low-risk group.ConclusionIn this study we demonstrated capacity for routinely reported CMR phenotypic markers and patient health information to be combined for the delivery of patient-specific predictions of time to HF hospitalization. This work supports an evolving migration toward multi-domain data collection for the delivery of personalized risk prediction at time of diagnostic imaging.

Catheter ablation of ventricular tachycardia in nonischemic cardiomyopathy with near-normal left ventricular ejection fraction.

Patients with idiopathic nonischemic cardiomyopathy (NICM) and near-normal left ventricular ejection fraction (LVEF) may develop ventricular tachycardia (VT). The purpose of this study was to describe procedural characteristics and outcomes in patients requiring ablation for NICM-related VT with near-normal LVEF compared to impaired LVEF. Over 8 years, 77 consecutive patients with NICM-related VT underwent catheter ablation. Of these patients, 47 had idiopathic NICM (20 near-normal LVEF, 27 impaired LVEF). Procedural characteristics and outcomes were compared. Mean age was 64 ± 12years, mean LVEF was 40% ± 14%, and 75% were male. In the near-normal LVEF group compared to the impaired LVEF group, LVEF was higher (54% ± 5% vs 30 ± 8%; P<.001), scar was predominantly located in the perivalvular left ventricle (LV) and basal septum (15/20 [75%]), was smaller in size [bipolar: 9.7 (6.2-32.4) cm2 vs 30.4 (21.1-37.6) cm2, P=.03; unipolar: 23.3 (6.6-39.9) cm2 vs 57.2 (42.2-74.9) cm2, P = .009], and required smaller areas of ablation [7.0 (5.9-14.2) cm2 vs 11.4 (8.5-16.7) cm2, P = .06]. Both groups experienced comparable procedure times, fluoroscopy doses, ablation times, VT cycle lengths, and acute success rates. After final ablation, VA-free survival was comparable between both groups (65% vs 63%; P=.63) at 12 months. Idiopathic NICM-related VT with near-normal LVEF was associated with discrete areas of arrhythmogenic, predominantly intramural, scar in the perivalvular LV and basal septum. Despite smaller scar, patients required similar ablation amounts and experienced comparable long-term outcomes compared to patients with idiopathic NICM-related VT and impaired LVEF. These findings underscore the "three-dimensionality" of substrate, whereby the intramural basal septum forms the third dimension and impacts ablation outcomes.

Transcaval access for the emergency delivery of 5.0 liters per minute mechanical circulatory support in cardiogenic shock.

The purpose of this study was to describe the feasibility and early outcomes of transcaval access for delivery of emergency mechanical circulatory support (MCS) in cardiogenic shock. Vascular access for implantation of MCS in patients with cardiogenic shock is often challenging due to peripheral arterial disease and vasoconstriction. Transcaval delivery of MCS may be an alternative. We describe a series of patients we implanted an Impella 5.0 device, on-table without CT planning, through a percutaneous transcaval access route. Ten patients with progressive or refractory cardiogenic shock underwent Impella 5.0 implantation via transcaval access. Demographic, clinical and procedural variables and in-hospital outcomes were collected. All ten underwent emergency implantation of the 7 mm diameter Impella 5.0 device via transcaval access. Six were women, with median age of 55.5 years (range, 29-69). Cardiogenic shock was attributed to idiopathic nonischemic cardiomyopathy (n = 4), myocarditis (n = 2), ischemic cardiomyopathy (n = 2), heart transplant rejection (n = 1), and unknown etiology (n = 1). Median duration of support was 92.1 hr (range, 21.2-165.4). Seven (70%) survived to device explant, with six (60%) surviving to access port closure and discharge. Among survivors, five recovered heart function and one received destination therapy left ventricular assist device. Transcaval access is feasible for emergency nonsurgical implantation of the Impella 5.0 device in cardiogenic shock with small or diseased iliofemoral arteries. This allows early institution of higher-flow MCS than conventional femoral artery implantation of the 3.5 L Impella CP device, and enables a bridge-to-recovery or bridge-to-destination strategy.

SUN-073 Autoimmune Polyendocrine Syndrome Type 2 Presenting As New Onset Systolic Heart Failure

Background: Autoimmune Polyendocrine Syndrome Type 2 (APS2) can present with a constellation of autoimmune disorders that evolve over time. Clinical case: A 35 year old woman with a history of Addison’s disease (diagnosed age 4), Hashimoto’s thyroiditis (diagnosed age 21) with longstanding hypothyroidism on levothyroxine, and polycystic kidney disease (PCKD) presented to the emergency department of another hospital with dyspnea and lower extremity edema. Echocardiogram revealed severe mitral regurgitation and left ventricular (LV) ejection fraction (EF) 40%. She was transferred to our hospital for further evaluation. Physical examination was notable for jugular venous distention, hyperpigmentation of palmar creases and buccal mucosa, minimal lower limb edema, and normal thyroid. Initial labs revealed TSH 0.83 (0.34-5.6 µIU/mL), FT4 0.55 (0.8-1.5 ng/dL), TT3 39 (87-178 ng/dL), TPO 28.1 (<5.6 IU/mL), Tg and TSH receptor Abs were negative, TSI 0.71 (<0.55 IU/L). A transesophageal echocardiogram demonstrated a LVEF of 44% with severe LV dilation and diffuse hypokinesis. Coronary angiography did not demonstrate obstructive disease. A cardiac MRI demonstrated global hypokinesis without areas of late gadolinium enhancement. Further history revealed in the 6 months prior to this presentation, she noted 30 lbs (13.6 kg) unintentional weight loss and amenorrhea. Three weeks prior to presentation she was started on lisinopril which caused wheezing and urticaria. She reported a recent adrenal crisis and was found to have a TSH <0.01, TT3 218, FT4 4.0, and elevated TSI. Iodine uptake scan demonstrated diffuse increased uptake, consistent with autoimmune thyrotoxicosis. She was started on methimazole, fludrocortisone, and increased dose of hydrocortisone. Differential diagnosis included hyperthyroid induced adrenal crisis and heart failure, autoimmune cardiomyopathy, or idiopathic nonischemic cardiomyopathy (NICM). Labs revealed negative RF, reticulin Ab, centromere Ab, tissue-transglutaminase, and myocardial Ab non-specific fluorescence. Early AM ACTH 203.5 (7.2-63.3 pg/mL), cortisol 4.0 (6.7-22.6 µg/dL). LH 14.94 (19.2-103 mIU/mL), FSH 6.5 (4.5-22.5 mIU/mL), HgbA1c 4.9%. Hct 30.7 (34-47%), vitamin B12 254 (211-911 pg/mL), homocysteine 17.7 (<11 µmol/L), methylmalonic acid 306 (0-378 nmol/L). Despite initiation of guideline directed medical therapy and volume optimization, an echocardiogram performed 6 weeks later demonstrated a LVEF of 43%. Conclusions: APS2 has typical manifestations of adrenal insufficiency, thyroiditis, and diabetes. This patient had clear evidence for APS2, but also presented with uncommon manifestations, including NICM. She also had wheezing with ACE inhibitor, a symptom of angioedema, not known to be associated with APS2. This case illustrates the importance of diagnosis of APS2 so other manifestations of the syndrome are recognized.

Sex-specific clinical outcomes after cardiac resynchronization therapy in left bundle branch block-associated idiopathic nonischemic cardiomyopathy: A NEOLITH II substudy.

Sex differences in clinical outcomes for left bundle branch block (LBBB)-associated idiopathic nonischemic cardiomyopathy (NICM) after cardiac resynchronization therapy (CRT) are not well described. A retrospective cohort study at an academic medical center included subjects with LBBB-associated idiopathic NICM who received CRT. Cox regression analyses estimated the hazard ratios (HRs) between sex and clinical outcomes. In 123 total subjects (mean age 62years, mean initial left ventricular ejection fraction 22.8%, 76% New York Heart Association class III, and 98% CRT-defibrillators), 55 (45%) were men and 68 (55%) were women. The median follow-up time after CRT was 72.4months. Similar risk for adverse clinical events (heart failure hospitalization, appropriate implantable cardioverter-defibrillator shock, appropriate antitachycardia pacing therapy, ventricular assist device implantation, heart transplantation, and death) was observed between men and women (HR, 1.20; 95% confidence interval [CI] 0.57-2.51; p=0.63). This persisted in multivariable analyses. Men and women had similar risk for all-cause mortality in univariable analysis, but men had higher risk in the final multivariable model that adjusted for age at diagnosis, QRS duration, and left ventricular end-diastolic dimension index (HR, 4.55; 95% CI, 1.26-16.39; p=0.02). The estimated 5-year mortality was 9.5% for men and 6.9% for women. In LBBB-associated idiopathic NICM, men have higher risk for all-cause mortality after CRT when compared to women.

Myocardial recovery after cardiac resynchronization therapy in left bundle branch block-associated idiopathic nonischemic cardiomyopathy: A NEOLITH II substudy.

Baseline predictors of myocardial recovery after cardiac resynchronization therapy (CRT) in left bundle branch block (LBBB)-associated idiopathic nonischemic cardiomyopathy (NICM) are unknown. A retrospective study included subjects with idiopathic NICM, left ventricular ejection fraction (LVEF) ≤35%, and LBBB. Myocardial recovery was defined as post-CRT LVEF ≥50%. Logistic regression analyses described associations between baseline characteristics and myocardial recovery. Cox regression analyses estimated the hazard ratio (HR) between myocardial recovery status and adverse clinical events. In 105 subjects (mean age 61years, 44% male, mean initial LVEF 22.6%±6.6%, 81% New York Heart Association class III, and 98% CRT-defibrillators), myocardial recovery after CRT was observed in 56 (54%) subjects. Hypertension, heart rate, and serum blood urea nitrogen (BUN) had negative associations with myocardial recovery in univariable analyses. These associations persisted in multivariable analysis: hypertension (odds ratio (OR), 0.40; 95% confidence interval (CI), 0.17-0.95; p=0.04), heart rate (OR per 10bpm, 0.69; 95% CI, 0.48-0.997; p=0.048), and serum BUN (OR per 1mg/dl, 0.94; 95% CI, 0.88-0.99; p=0.04). Subjects with post-CRT LVEF ≥50%, when compared to <50%, had lower risk for adverse clinical events (heart failure hospitalization, appropriate implantable cardioverter-defibrillator shock, appropriate anti-tachycardia pacing therapy, ventricular assist device implantation, heart transplantation, and death) over a median follow-up of 75.9months (HR, 0.38; 95% CI, 0.16-0.88; p=0.02). In LBBB-associated idiopathic NICM, myocardial recovery after CRT was associated with absence of hypertension, lower heart rate, and lower serum BUN. Those with myocardial recovery had fewer adverse clinical events.

New‐onset left bundle branch block‐associated idiopathic nonischemic cardiomyopathy and time from diagnosis to cardiac resynchronization therapy: The NEOLITH II study

The optimal timing for cardiac resynchronization therapy (CRT) after diagnosis of new-onset left bundle branch block (LBBB)-associated idiopathic nonischemic cardiomyopathy (NICM) and treatment with guideline-directed medical therapy (GDMT) is unknown. The purpose of this study was to describe relationships between time from diagnosis to CRT and outcomes in new-onset LBBB-associated idiopathic NICM with left ventricular ejection fraction (LVEF) ≤35%. A retrospective cohort study examined associations between time from diagnosis to CRT (≤9 months vs>9 months) and clinical and echocardiographic outcomes. In 123 subjects with LBBB-associated idiopathic NICM, time from diagnosis to CRT was ≤9 months in 60 (49%) subjects and9 months in 63 (51%) subjects. Clinical outcomes were similar for those implanted ≤9 months versus>9 months for adverse clinical events (hazard ratio [HR], 0.85; 95% confidence interval [CI], 0.41-1.78; P=0.67) and all-cause mortality (HR, 0.57; 95% CI, 0.19-1.70; P=0.31). Multivariable analyses demonstrated similar results. In 105 subjects with post-CRT echocardiograms, LVEF improvement to>35% was more likely in those implanted ≤9 months when compared to>9 months (odds ratio [OR], 3.53; 95% CI, 1.32-9.46; P=0.01). This association persisted in the final multivariable model adjusted for age at diagnosis, sex, QRS duration, post-GDMT LVEF, and time from CRT to post-CRT echocardiogram (OR, 5.10; 95% CI, 1.71-15.22; P=0.004). In LBBB-associated idiopathic NICM, earlier CRT implantation was associated with more favorable cardiac remodeling. Delaying CRT may miss a critical period to halt and reverse progressive myocardial damage.

Predictors and implications of early left ventricular ejection fraction improvement in new-onset idiopathic nonischemic cardiomyopathy with narrow QRS complex: A NEOLITH substudy.

Predictors and implications of early left ventricular ejection fraction (LVEF) improvement with guideline-directed medical therapy (GDMT) in new-onset idiopathic nonischemic cardiomyopathy (NICM) with narrow QRS complex are not well described. The objectives were to describe predictors of LVEF improvement after 3months on GDMT and adverse cardiac events based on post-GDMT LVEF status (≤35% vs. >35%). A retrospective cohort study was performed in subjects with new-onset NICM, LVEF ≤35%, and narrow QRS complex. Associations for baseline variables with post-GDMT LVEF improvement and absolute change in LVEF (∆LVEFGDMT ) were assessed. Cox proportional hazards models assessed associations for post-GDMT LVEF status with adverse cardiac events. In 70 subjects, 31 (44%) had post-GDMT LVEF ≤35% after a median follow-up time of 97.5days (interquartile range, 84-121days). In final multivariable models, severely dilated left ventricular end-diastolic diameter (LVEDD), compared with normal LVEDD, strongly predicted post-GDMT LVEF ≤35% (odds ratio, 7.77; 95% confidence interval [CI], 1.39-43.49; p=.02) and ∆LVEFGDMT (β=-15.709; standard error=4.622; p=.001). Subjects with post-GDMT LVEF ≤35% were more likely to have adverse cardiac events over a median follow-up time of 970.5days (unadjusted hazard ratio, 2.15; 95% CI, 0.93-4.96; p=.07). In the post-GDMT LVEF ≤35% group, 9 of 26 subjects (35%) had long-term LVEF>35%. In new-onset NICM with narrow QRS complex, nondilated LVEDD predicted early LVEF improvement. Those with post-GDMT LVEF ≤35% had higher risk of adverse cardiac events, but a substantial proportion demonstrated continued long-term LVEF improvement.

A Matched Cohort Study of Patients With End-Stage Heart Failure from Anthracycline-Induced Cardiomyopathy Requiring Advanced Cardiac Support

Anthracycline-induced cardiomyopathy (AIC) may progress to end-stage heart failure requiring mechanical circulatory support or orthotopic heart transplantation (OHT). Previous studies have described important clinical differences between AIC and nonischemic cardiomyopathy (NIC) cohorts requiring these advanced interventions. Therefore, we sought to extend this literature by comparing echocardiographic parameters, treatment strategies, and the prognosis between matched patients from these cohorts. This is a retrospective matched cohort study. All patients who received a ventricular assist device or OHT at a large Canadian center were reviewed (n= 421; 1988 to 2015) and subjects with clinical and pathologic evidence of AIC were included (n= 17, 4.0%). A comparison cohort with idiopathic NIC from the same database, matched 3:1 for age, gender, ethnicity, and year of heart failure onset was selected. The Mann-Whitney rank-sum and Fisher's exact tests were used for comparisons. Patients with AIC were predominantly women (70.6%) with heart failure diagnosed at age 40.2 ± 15.8 and 8.3 ± 8.9years after anthracycline treatment. Compared with NIC, no differences were seen in co-morbidities, echocardiographic measures, the proportion of patients receiving a defibrillator, ventricular assist device, or OHT, the incidence of graft failure, and all-cause mortality. In contrast to other studies, AIC was not associated with a higher incidence of right ventricular dysfunction. A greater proportion of patients with AIC developed cancer (recurrence or new primary) post-OHT (21.4% vs 2.3%, p= 0.042). In conclusion, we demonstrate that when matched cohortsof patients with end-stage heart failure secondary to AIC and idiopathic NIC are compared, they are similar with respect to co-morbidities, degree of ventricular dysfunction, and advanced therapeutics used. The prognosis with OHT is also similar.

New-onset left bundle branch block–associated idiopathic nonischemic cardiomyopathy and left ventricular ejection fraction response to guideline-directed therapies: The NEOLITH study

Left ventricular ejection fraction (LVEF) response to guideline-directed medical therapy (GDMT) and to early cardiac resynchronization therapy (CRT) in new-onset idiopathic nonischemic cardiomyopathy (NICM) and left bundle branch block (LBBB) is not well described. CRT is recommended if LVEF remains ≤35% after at least 3 months of GDMT. The purpose of this study was to describe LVEF response to GDMT at 3 months and to early CRT in new-onset LBBB-associated idiopathic NICM. A retrospective cohort study was performed in subjects with new-onset idiopathic NICM, LVEF ≤35%, and LBBB or narrow (<120 ms) QRS complex morphology. LVEF response between groups was evaluated with log-binomial and linear regression. LVEF response within groups was evaluated using the paired Student t test. In 102 subjects (70 with narrow QRS complex and 32 with LBBB), post-GDMT LVEF was >35% in 39 narrow QRS complex subjects (56%) and 2 LBBB subjects (6%) (P < .0001). The absolute difference between post-GDMT LVEF and initial LVEF was greater in the narrow QRS complex group (16.1% ± 14.6% vs. 3.3% ± 10.7%; P < .0001). Narrow QRS complex, referenced to LBBB, was significantly associated with post-GDMT LVEF >35% (relative risk 10.30; 95% confidence interval 2.63-40.27; P = .0008) and absolute difference between post-GDMT LVEF and initial LVEF (β = 16.296; standard error = 2.977; P < .0001) in final multivariable analyses. CRT super-response, defined as post-CRT LVEF ≥50%, was observed in 8 of LBBB subjects (35%) who received CRT. GDMT did not significantly improve LVEF in new-onset LBBB-associated idiopathic NICM at 3 months. Most remained candidates for CRT, and a high percentage were super-responders. Optimal timing for CRT implantation requires further investigation.

Characteristics, Treatments, and Outcomes of Hospitalized Heart Failure Patients Stratified by Etiologies of Cardiomyopathy

ObjectivesThe authors sought to describe characteristics, treatments, and in-hospital outcomes of hospitalized heart failure (HF) patients stratified by etiology. BackgroundWhether characteristics and outcomes of HF patients differ by cardiomyopathy etiology is unknown. MethodsThe authors analyzed data on 156,013 hospitalized HF patients from 319 U.S. hospitals participating in Get With The Guidelines–HF between 2005 and 2013. Characteristics, treatments, and in-hospital outcomes were assessed by HF etiology. Standard regression techniques adjusted for site and patient-level characteristics were used to examine association between HF etiology and in-hospital outcomes. ResultsMedian age was 75 years, 69.2% were white, and 49.5% were women. Overall, 92,361 patients (59.2%) had ischemic cardiomyopathy and 63,652 patients (40.8%) had nonischemic cardiomyopathy (NICM). Hypertensive (n = 28,141; 48.5%) and idiopathic (n = 17,808; 30.7%) cardiomyopathies accounted for the vast majority of NICM patients. Post-partum (n = 209; 0.4%), viral (n = 447; 0.8%), chemotherapy (n = 721; 1.2%), substance abuse (n = 2,653; 4.6%), familial (n = 556; 1.0%), and other (n = 7,523; 13.0%) etiologies were far less frequent. There were significant differences in baseline characteristics between those with ischemic cardiomyopathy compared with NICM with respect to age (76 years vs. 72 years), sex (44.4% vs. 56.9% women), and ejection fraction (38% vs. 45%). Risk-adjusted quality of care provided to eligible patients varied minimally by etiology. Similarly, in-hospital mortality did not differ among ischemic compared with NICM patients. However, among NICM patients, only hypertensive cardiomyopathy had a lower mortality rate compared with idiopathic NICM (adjusted odds ratio: 0.83; 95% confidence interval: 0.71 to 0.97). ConclusionsCharacteristics of hospitalized HF patients vary by etiology. Both risk-adjusted quality of care and in-hospital outcomes did not differ by etiology.

FEATURE TRACKING-BASED STRAIN ANALYSIS PREDICTS THE PRESENCE OF MYOCARDIAL FIBROSIS AMONG PATIENTS WITH NON-ISCHEMIC CARDIOMYOPATHY

Abnormal myocardial deformation has been described in the presence of regional fibrosis, as detected by late gadolinium enhancement (LGE) cardiac magnetic resonance imaging (CMR) in patients with previous infarction, Fabry’s disease and hypertrophic cardiomyopathy. Mid-wall striae pattern fibrosis on LGE imaging has been shown to predict adverse cardiovascular outcomes among patients with non-ischemic cardiomyopathy. However, macroscopic mid-wall fibrosis is a late pathologic finding and requires administration of gadolinium based contrast agent. Non-contrast dependent markers heralding adverse remodeling are desired. In this study we describe a novel strain analysis tool employing feature tracking to predict the presence of mid-wall fibrosis in patients with non-ischemic cardiomyopathy. CMR imaging was performed in 117 patients with idiopathic non-ischemic cardiomyopathy, defined as a left ventricular ejection fraction (LVEF) <55% by CMR with no prior history of myocardial infarction and no CMR findings of ischemic or other specific cardiomyopathy states (ie. hypertrophic cardiomyopathy, amyloidosis, sarcoidosis). Blinded quantitative analysis was performed using a prototype version of a commercial software (cvi42, version 4.1.5 M192, Calgary, Alberta, Canada). Left ventricular regional strain analysis was performed to obtain both radial and circumferential strain of a mid-ventricular short axis slice cine image (Figure 1). Volumetric analysis of sequential short axis cine images was also performed. LGE images were visually scored for the presence of mid-wall striae fibrosis. Mean age was 57.8 +/- 14.5 years and 60 % of patients were male. CMR characteristics are summarized in Table 1. Mid-wall striae fibrosis was identified in 48 patients (41 %). These patients had greater indexed LV end diastolic and systolic volumes and total scar volume with lower LV and RV ejection fraction. Compared to patients without midwall striae fibrosis, radial and circumferential strain values were significantly lower in the mid anteroseptal segments among patients with midwall striae fibrosis despite corresponding anterolateral strain values being similar (Table 1). On multivariate analysis, patients with midwall striae fibrosis had a significantly lower anteroseptal to anterolateral strain ratio (AASR) for both radial (0.61±0.41 vs. 0.37±0.32, p=0.024) and circumferential strain (0.66±0.36 vs. 0.42±0.29, p=0.015). Of note, 15 (22%) patients had a low AASR despite having no midwall striae fibrosis on LGE imaging. AASR is strongly associated with the presence of midwall striae fibrosis in patients with non-ischemic cardiomyopathy. The prognostic utility of this novel imaging marker warrants future study within a prospective multi-centre study.View Large Image Figure ViewerDownload (PPT)

Abstract 18878: Development of a Unique Mode of Cardiac Remodeling in Muscular Dystrophy Patients

The muscular dystrophies (MD) represent an array of inherited myogenic disorders involving mutations and dysregulations of a variety of cytoskeleton or nuclear proteins. Many MD patients also develop a commitant cardiomyopathy. Despite the high incidence of end-stage cardiomyopathy in MD patients there is limited data regarding the mode of maladaptive cardiac remodeling that develops in these patients. In this retrospective study, we examined the hypothesis that MD patients with a cardiomyopathy develop a unique mode of cardiac remodeling as compared to patients with other forms of nonischemic cardiomyopathy. We examined the cardiac MRIs of 3 cohorts (N = 35 per cohort): patients with neuromuscular disorders with associated cardiomyopathy; patients with primary idiopathic nonischemic cardiomyopathy (NICM); and healthy patients from the Dallas Heart Study (DHS). The cardiac MRIs in each group were reviewed, assessing objective measurements of left ventricular ejection fraction (LVEF), mass (LVM), and end diastolic volume (LVEDV). LVM and LVEDV were indexed for body surface area. In addition, left ventricular concentricity 0.67 (LV Conc 0.67 = LVM / LVEDV 0.67 ), a surrogate marker for wall thickness known to decrease in advanced nonischemic heart failure, was computed for each patient. Despite a preserved ejection fraction in the neuromuscular cohort compared to the NICM cohort (58% vs. 30 %, p&lt;0.05), both displayed similar reduced LV Conc 0.67 (4.69 ± 1.05 and 5.16 ± 1.47) compared to the DHS cohort (7.27 ± 0.83). However, whereas the nonischemic cohort demonstrated hypertrophy with marked dilation (95.8 vs. 84.6 g/m 2 and 119.4 vs. 54.7 mL/m 2 , DHS comparison, p&lt;0.05), the neuromuscular cohort demonstrated a reduced cardiac mass (65.6 vs. 84.6 g/m 2 , p&lt;0.05) with only moderate dilation (74.5 vs. 54.7 mL/m 2 , p&lt;0.05) compared to the DHS population. In conclusion, our data suggests that MD patients develop a unique mode of cardiac remodeling and highlights that novel signaling pathways are involved in the development of cardiomyopathy in these patients.

Diffuse myocardial fibrosis, but not focal fibrosis identified with delayed enhancement, is an independent predictor of LV reversed remodeling in patients with idiopathic non-ischemic cardiomyopathy

Methods We performed CMR in 24 patients with idiopathic nonischemic cardiomyopathy (16 men, mean age 58±11 years) and also in 12 healthy volunteers as control subjects. T1 mapping was performed with post-contrast Look-Locker gradient echo. Baseline echocardiography as well as hemodynamic and metabolic data were collected at the time of CMR. Patients were followed over a median time of 8 months for LVRR which was defined as a left ventricular ejection fraction (LVEF) increase of ≥10 U and a decrease in indexed left ventricular end-diastolic diameter (LVEDD) of ≥10% or indexed LVEDD of < 33 mm/m at 24 months. A multivariable logistic regression analysis was performed to identify associations with LVRR.

Successful Long-Term Use of Sitagliptin for the Treatment of New-Onset Diabetes Mellitus After Solid Organ Transplantation: A Case Report

Aims To describe 2.5 years of exposure to sitagliptin on glycemic control, immunosuppressive therapy, and adverse events following solid organ transplantation. Case report A 63-year-old Caucasian male received an orthotopic heart transplantation in June of 2006 secondary to idiopathic nonischemic cardiomyopathy. He was diagnosed with new-onset diabetes mellitus after transplantation (NODAT). Sitagliptin monotherapy was initiated in August 2007 and continued for 2.5 years. Results Hemoglobin A 1c increased from 5.8% to 6.1%, but the recommended glycemic target of <7% was maintained over time and improvements in fasting home blood glucose monitoring values were achieved. Tacrolimus concentrations were not altered. Only minor dose adjustments to tacrolimus and mycophenolate mofetil were required. Maintenance corticosteroid dose remained unchanged and there was no evidence of biopsy-proven acute rejection. No adverse events were reported. Discussion This case report demonstrates that long-term sitagliptin treatment for NODAT may be effective, safe, and well tolerated in solid organ transplant recipients.

Colonic perforation from left ventricular assist device: a rare complication

A patient with idiopathic non-ischemic cardiomyopathy had a left ventricular assist device (LVAD) implanted, while awaiting cardiac transplantation. The patient had been stable following a complicated and prolonged postoperative course, but was admitted to the hospital for suspected low-grade LVAD-related infection. Work-up for sepsis was suspicious for perforated viscus. An exploratory laparotomy revealed a perforated transverse colon with gross spillage of succus. Although infectious complications following LVAD implantation are common, sepsis as a result of gastrointestinal perforation secondary to LVAD erosion is not. This first report of viscus perforation despite the use of a Gore-Tex wrap highlights a rare complication of LVAD therapy.