Contemporary Outcomes of Acute Ischemic Stroke in Atrial Fibrillation Patients on Anticoagulation

BACKGROUND

Long-term anticoagulation (AC) therapy reduces the risk of stroke in patients with Atrial Fibrillation (AF). However, data on the impact of AC on in-hospital stroke outcomes is lacking.

METHODS

The National Inpatient Sample was used to identify adult inpatients with AF and a primary diagnosis of ischemic stroke between 2016 and 2020. Data was stratified between AC users and nonusers. A multivariate regression model was used to describe the in-hospital outcomes, adjusting for significant comorbidities.

RESULTS

A total of 655,540 hospitalizations with AF and a primary hospitalization diagnosis of ischemic stroke were included, of which 194,560 (29.7%) were on long-term AC. Patients on AC tended to be younger (mean age, 77 vs 78), had a higher average CHA2DS2VASc score (4.48 vs 4.20), higher rates of hypertension (91% vs 88%), hyperlipidemia (64% vs 59%), and heart failure (34% vs 30%) compared to patients not on long-term AC. Use of AC was associated with decreased in-hospital mortality (aOR [95% CI]: 0.62 [0.60 - 0.63]), decreased stroke severity (mean NIHSS, 8 vs 10), decreased use of tPA (aOR 0.42 [0.41 - 0.43]), mechanical thrombectomy (aOR 0.85 [0.83 - 0.87]), intracranial hemorrhage (aOR 0.69 [0.67 - 0.70]), gastrointestinal bleeding (aOR 0.74 [0.70 - 0.77]), and discharge to skilled nursing facilities (aOR 0.90 [0.89 - 0.91]), compared to patients not on AC (P<0.001 for all comparisons).

CONCLUSION

Among patients with AF admitted for acute ischemic stroke, AC use prior to stroke was associated with decreased in-hospital mortality, decreased stroke severity, decreased discharge to SNF, and fewer stroke-related and bleeding complications.

Electrogram morphology recurrence guided catheter ablation for repeat ablation of persistent atrial fibrillation

BACKGROUND

There are no standard mapping approaches for patients with persistent atrial fibrillation (PeAF), particularly after failed prior catheter ablation (CA). In this study, we assess the feasibility of using Electrogram Morphology Recurrence (EMR) to guide ablation.

METHODS

Ten patients with recurrent PeAF after prior CA underwent detailed mapping of both atria during PeAF using the PentaRay (4 mm interelectrode spacing) and 3D mapping with CARTO. At each site, 15 s recordings were made. Custom software identified each electrogram and cross-correlation was used to identify the most recurrent electrogram morphology from which the % recurrence and cycle length of the most repeatable morphology (CLR) was calculated. Sites of shortest CLR and sites within 5 ms of shortest CLR with recurrence ≥ 80% were used to inform CA strategy.

RESULTS

A mean of 342.9 ± 131.9 LA and 328.6 ± 91.5 RA sites were recorded per patient. Nine had PV reconnection. Shortest CLR sites guided ablation in 6/10 patients while 1 patient failed to fulfill shortest CLR criteria, and another 3 did not undergo CA guided by shortest CLR due to operator preference. On 12-month follow-up, all 4 patients without shortest CLR guided CA had recurrent PeAF. Of the 6 patients with shortest CLR guided CA, 5 patients did not have recurrent PeAF (p = 0.048), although 1 had paroxysmal AF and 2 had atypical atrial flutter.

CONCLUSION

EMR is a feasible, novel technique to guide CA in patients with PeAF. Further evaluation is needed to provide an electrogram-based method for mapping guided targeted ablation of key areas.

Comparison of electrogram characteristics in persistent atrial fibrillation

INTRODUCTION

Multiple analysis techniques evaluate electrograms during atrial fibrillation (AF), but none have been established to guide catheter ablation. This study compares electrogram properties recorded from multiple right (RA) and left atrial (LA) sites.

METHODS

Multisite LA/RA mapping (281 ± 176/239 ± 166 sites/patient) was performed in 42 patients (30 males, age 63 ± 9 years) undergoing first (n = 32) or redo-AF ablation (n = 10). All electrogram recordings were visually reviewed and artifactual signals were excluded leaving a total of 21 846 for analysis. Electrogram characteristics evaluated were cycle length (CL), amplitude, Shannon's entropy (ShEn), fractionation interval, dominant frequency, organizational index, and cycle length of most recurrent morphology (CLR ) from morphology recurrence plot analysis.

RESULTS

Electrogram characteristics were correlated to each other. All pairwise comparisons were significant (p < .001) except for dominant frequency and CLR (p = .59), and amplitude and dominant frequency (p = .38). Only ShEn and fractionation interval demonstrated a strong negative correlation (r = -.94). All other pairwise comparisons were poor to moderately correlated. The relationships are highly conserved among patients, in the RA versus LA, and in those undergoing initial versus redo ablations. Antiarrhythmic drug therapy did not have a significant effect on electrogram characteristics, except minimum ShEn. Electrogram characteristics associated with ablation outcome were shorter minimum CLR , lower minimum ShEn, and longer mimimum CL. There was minimal overlap between the top 10 sites identified by one electrogram characteristic and the top 10 sites identified by the other 10 characteristics.

CONCLUSION

Multiple techniques can be employed for electrogram analysis in AF. In this analysis of eight different electrogram characteristics, seven were poorly to moderately correlated and do not identify similar locations. Only some characteristics were predictive of ablation outcome. Further studies to consider electrogram properties, perhaps in combination, for categorizing and/or mapping AF are warranted.

The Cost of Return to Play Protocols in Collegiate Athletes Recovering from Coronavirus Disease 2019

INTRODUCTION/PURPOSE

SARS-CoV-2 infection (COVID-19) can result in myocarditis. Protocols were developed to allow competitive athletes to safely return to play (RTP) after a COVID-19 infection, but the financial impact of these protocols is unknown. Our objective was to determine the differential cost of post-COVID-19 RTP protocols for competitive collegiate athletes.

METHODS

This multicenter retrospective cohort study of clinical evaluation of 295 athletes after COVID-19 infection was performed at four institutions with three RTP protocols. Costs were calculated using adjusted Center for Medicare and Medicaid Services pricing. All athletes underwent electrocardiogram and clinical evaluation. A tiered approach performed cardiac imaging and biomarker analysis for major symptoms. A universal transthoracic echocardiogram (TTE) approach performed TTE and biomarkers for all athletes. A universal exercise stress echocardiogram (ESE) approach performed ESE and biomarkers for all athletes.

RESULTS

The cost per athlete was $632.51 ± 651.80 ($44,908 total) in tiered group (n = 71), $1,072.30 ± 517.93 ($87,928 total) in the universal TTE group (n = 82), and $1357.38 ± 757.05 ($192,748 total) in the universal ESE group (n = 142) (P < 0.001). Extrapolated national costs for collegiate athletes would be $39 to 64 million higher for universal imaging approaches versus a tiered approach. Only seven athletes had probable/possible myocarditis with no significant difference between approaches.

CONCLUSIONS

Cardiac screening in collegiate athletes after COVID-19 infection resulted in significant cost to the health care system. A tiered-based approach was more economical, and a universal exercise echocardiogram group detected slightly more myocardial abnormalities by cardiac magnetic resonance imaging. The clinical consequences of these approaches are unknown.

Long-term cardiac surveillance and outcomes of COVID-19 patients

Acute cardiac manifestions of COVID-19 have been well described, while chronic cardiac sequelae remain less clear. Various studies have shown conflicting data on the prevalence of new or worsening cardiovascular disease, myocarditis or cardiac dysrhythmias among patients recovered from COVID-19. Data are emerging that show that patients recovering from COVID-19 have an increased incidence of myocarditis and arrhythmias after recovery from COVID-19 compared with the control groups without COVID-19. The incidence of myocarditis after COVID-19 infection is low but is still significantly greater than the incidence of myocarditis from a COVID-19 vaccine. There have been several studies of athletes who underwent a variety of screening protocols prior to being cleared to return to exercise and competition. The data show possible, probable or definite myocarditis or cardiac injury among 0.4–3.0% of the athletes studied. Recent consensus statements suggest that athletes with full recovery and absence of cardiopulmonary symptoms may return to exercise and competition without cardiovascular testing. In conclusion, patients with COVID-19 may be expected to have an increased risk of cardiovascular disease, myocarditis or arrhythmias during the convalescent phase. Fortunately, the majority of patients, including athletes may return to their normal activity after recovery from COVID 19, in the absence of persisting cardiovascular symptoms.

The impact of patient sex on the response to intramyocardial mesenchymal stem cell administration in patients with non-ischaemic dilated cardiomyopathy

AIMS

Sex differences impact the occurrence, presentation, prognosis, and response to therapy in heart disease. Particularly, the phenotypic presentation of patients with non-ischaemic dilated cardiomyopathy (NIDCM) differs between men and women. However, whether the response to mesenchymal stem cell (MSC) therapy is influenced by sex remains unknown. We hypothesize that males and females with NIDCM respond similarly to MSC therapy.

METHODS AND RESULTS

Male (n = 24) and female (n = 10) patients from the POSEIDON-DCM trial who received MSCs via transendocardial injections were evaluated over 12 months. Endothelial function was measured at baseline and 3 months post-transendocardial stem cell injection (TESI). At baseline, ejection fraction (EF) was lower (P = 0.004) and end-diastolic volume (EDV; P = 0.0002) and end-systolic volume (ESV; P = 0.0002) were higher in males vs. females. In contrast, baseline demographic characteristics, Minnesota Living with Heart Failure Questionnaire (MLHFQ), and 6-min walk test (6MWT) were similar between groups. EF improved in males by 6.2 units (P = 0.04) and in females by 8.6 units (P = 0.04; males vs. females, P = 0.57). EDV and ESV were unchanged over time. The MLHFQ score, New York Heart Association (NYHA) class, endothelial progenitor cell-colony forming units, and serum tumour necrosis factor alpha improved similarly in both groups.

CONCLUSION

Despite major differences in phenotypic presentation of NIDCM in males and females, this study is the first of its kind to demonstrate that MSC therapy improves a variety of parameters in NIDCM irrespective of patient sex. These findings have important clinical and pathophysiologic implications regarding the impact of sex on responses to cell-based therapy for NIDCM.

A Phase II study of autologous mesenchymal stromal cells and c-kit positive cardiac cells, alone or in combination, in patients with ischaemic heart failure: the CCTRN CONCERT-HF trial

AIMS

CONCERT-HF is an NHLBI-sponsored, double-blind, placebo-controlled, Phase II trial designed to determine whether treatment with autologous bone marrow-derived mesenchymal stromal cells (MSCs) and c-kit positive cardiac cells (CPCs), given alone or in combination, is feasible, safe, and beneficial in patients with heart failure (HF) caused by ischaemic cardiomyopathy.

METHODS AND RESULTS

Patients were randomized (1:1:1:1) to transendocardial injection of MSCs combined with CPCs, MSCs alone, CPCs alone, or placebo, and followed for 12 months. Seven centres enrolled 125 participants with left ventricular ejection fraction of 28.6 ± 6.1% and scar size 19.4 ± 5.8%, in New York Heart Association class II or III. The proportion of major adverse cardiac events (MACE) was significantly decreased by CPCs alone (-22% vs. placebo, P = 0.043). Quality of life (Minnesota Living with Heart Failure Questionnaire score) was significantly improved by MSCs alone (P = 0.050) and MSCs + CPCs (P = 0.023) vs. placebo. Left ventricular ejection fraction, left ventricular volumes, scar size, 6-min walking distance, and peak oxygen consumption did not differ significantly among groups.

CONCLUSIONS

This is the first multicentre trial assessing CPCs and a combination of two cell types from different tissues in HF patients. The results show that treatment is safe and feasible. Even with maximal guideline-directed therapy, both CPCs and MSCs were associated with improved clinical outcomes (MACE and quality of life, respectively) in ischaemic HF without affecting left ventricular function or structure, suggesting possible systemic or paracrine cellular mechanisms. Combining MSCs with CPCs was associated with improvement in both these outcomes. These results suggest potential important beneficial effects of CPCs and MSCs and support further investigation in HF patients.

Association of SGLT2 inhibitors with arrhythmias and sudden cardiac death in patients with type 2 diabetes or heart failure: A meta-analysis of 34 randomized controlled trials

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors (SGLT2is) reduce hospitalizations and death from heart failure (HF), but their effect on arrhythmia expression has been poorly investigated.

OBJECTIVE

The purpose of this study was to evaluate the association of SGLT2is with arrhythmias in patients with type 2 diabetes mellitus (T2DM) or HF.

METHODS

We searched PubMed and ClinicalTrials.gov. Two independent investigators identified randomized double-blind trials that compared SGLT2is with placebo or active control for adults with T2DM or HF. Primary outcomes were incident atrial arrhythmias, ventricular arrhythmias (VAs), and sudden cardiac death (SCD).

RESULTS

We included 34 randomized (25 placebo-controlled and 9 active-controlled) trials with 63,166 patients (35,883 SGLT2is vs 27,273 control: mean age 53-67 years; 63% male). Medications included canagliflozin, dapagliflozin, empagliflozin, or ertugliflozin. Except for 1 study of HF, all patients had T2DM. Follow-up ranged from 24 weeks to 5.7 years. The cumulative incidence of events was low: 3.6, 1.4, and 2.5 per 1000 patient-years for atrial arrhythmias, VAs and SCD, respectively. SGLT2i therapy was associated with a significant reduction in the risk of incident atrial arrhythmias (odds ratio 0.81; 95% confidence interval 0.69-0.95; P = .008) and the "SCD" component of the SCD outcome (odds ratio 0.72; 95% confidence interval 0.54-0.97; P = .03) compared with control. There was no significant difference in incident VA or the "cardiac arrest" SCD component between groups.

CONCLUSION

SGLT2is are associated with significantly reduced risks of incident atrial arrhythmias and SCD in patients with T2DM. Prospective trials are warranted to confirm the antiarrhythmic effect of SGLT2is and whether this is a class or drug-specific effect.

Demographic representation in clinical trials for cell-based therapy

Inclusion of women and minorities in clinical research is critical to fully assess the safety and efficacy of innovative therapies. With inadequate representation of demography, generalizability is impaired since pharmacokinetics and pharmacodynamics differ in these patient populations. This study was designed to analyze the voluntary participation rates of different demographic groups in cell-based therapy clinical trials conducted by the Interdisciplinary Stem Cell Institute (ISCI) at the University of Miami, Miller School of Medicine. ISCI conducted eight clinical trials between 2007 and 2017. The trials enrolled patients with ischemic and non-ischemic cardiomyopathy, idiopathic pulmonary fibrosis (IPF), aging-frailty, and Type-2 Diabetes. Participants received cell-based therapy (n = 218) or placebo (n = 33). Among the 251 participants, 29.5% were Hispanic and 20% were women. The proportion of individuals participating in each trial was compared to that of the respective disease populations attending University of Miami Health System clinics to calculate the participation to prevalence ratio (PPR). Distribution of women accurately reflected the population attending the University of Miami Health System in trials for dilated cardiomyopathy (DCM) and aging-frailty but was under-represented in others. Similarly, Hispanics and whites were accurately represented in three of the five disease fields, with Hispanics under-represented in frailty and diabetes, and whites over-represented in DCM and IPF. Black patients were accurately represented in the diabetes trial but were under-represented in all others. This study provides insight into challenges of achieving representative inclusion in research. Novel community engagement strategies are necessary to improve inclusion of women and under-represented minorities in clinical research of cell-based therapy.

COVID-19 cardiac injury: Implications for long-term surveillance and outcomes in survivors

Up to 20%-30% of patients hospitalized with coronavirus disease 2019 (COVID-19) have evidence of myocardial involvement. Acute cardiac injury in patients hospitalized with COVID-19 is associated with higher morbidity and mortality. There are no data on how acute treatment of COVID-19 may affect the convalescent phase or long-term cardiac recovery and function. Myocarditis from other viral pathogens can evolve into overt or subclinical myocardial dysfunction, and sudden death has been described in the convalescent phase of viral myocarditis. This raises concerns for patients recovering from COVID-19. Some patients will have subclinical and possibly overt cardiovascular abnormalities. Patients with ostensibly recovered cardiac function may still be at risk of cardiomyopathy and cardiac arrhythmias. Screening for residual cardiac involvement in the convalescent phase for patients recovered from COVID-19-associated cardiac injury is needed. The type of testing and therapies for post COVID-19 myocardial dysfunction will need to be determined. Therefore, now is the time to plan for appropriate registries and clinical trials to properly assess these issues and prepare for long-term sequelae of "post-COVID-19 cardiac syndrome."

Allogeneic Mesenchymal Cell Therapy in Anthracycline-Induced Cardiomyopathy Heart Failure Patients: The CCTRN SENECA Trial

BACKGROUND

Anthracycline-induced cardiomyopathy (AIC) may be irreversible with a poor prognosis, disproportionately affecting women and young adults. Administration of allogeneic bone marrow-derived mesenchymal stromal cells (allo-MSCs) is a promising approach to heart failure (HF) treatment.

OBJECTIVES

SENECA (Stem Cell Injection in Cancer Survivors) was a phase 1 study of allo-MSCs in AIC.

METHODS

Cancer survivors with chronic AIC (mean age 56.6 years; 68% women; NT-proBNP 1,426 pg/ml; 6 enrolled in an open-label, lead-in phase and 31 subjects randomized 1:1) received 1 × 10⁸ allo-MSCs or vehicle transendocardially. Primary objectives were safety and feasibility. Secondary efficacy measures included cardiac function and structure measured by cardiac magnetic resonance imaging (CMR), functional capacity, quality of life (Minnesota Living with Heart Failure Questionnaire), and biomarkers.

RESULTS

A total of 97% of subjects underwent successful study product injections; all allo-MSC-assigned subjects received the target dose of cells. Follow-up visits were well-attended (92%) with successful collection of endpoints in 94% at the 1-year visit. Although 58% of subjects had non-CMR compatible devices, CMR endpoints were successfully collected in 84% of subjects imaged at 1 year. No new tumors were reported. There were no significant differences between allo-MSC and vehicle groups with regard to clinical outcomes. Secondary measures included 6-min walk test (p = 0.056) and Minnesota Living with Heart Failure Questionnaire score (p = 0.048), which tended to favor the allo-MSC group.

CONCLUSIONS

In this first-in-human study of cell therapy in patients with AIC, transendocardial administration of allo-MSCs appears safe and feasible, and CMR was successfully performed in the majority of the HF patients with devices. This study lays the groundwork for phase 2 trials aimed at assessing efficacy of cell therapy in patients with AIC.

Atrial Myopathy Underlying Atrial Fibrillation

While AF most often occurs in the setting of atrial disease, current assessment and treatment of patients with AF does not focus on the extent of the atrial myopathy that serves as the substrate for this arrhythmia. Atrial myopathy, in particular atrial fibrosis, may initiate a vicious cycle in which atrial myopathy leads to AF, which in turn leads to a worsening myopathy. Various techniques, including ECG, plasma biomarkers, electroanatomical voltage mapping, echocardiography, and cardiac MRI, can help to identify and quantify aspects of the atrial myopathy. Current therapies, such as catheter ablation, do not directly address the underlying atrial myopathy. There is emerging research showing that by targeting this myopathy we can help decrease the occurrence and burden of AF.

Network meta-analysis of His bundle, biventricular, or right ventricular pacing as a primary strategy for advanced atrioventricular conduction disease with normal or mildly reduced ejection fraction

INTRODUCTION

Although right ventricular pacing (RVP) may impair ventricular function, it is commonly used for advanced atrioventricular block (AVB) and normal or mildly reduced ejection fraction (EF). We aimed to compare His bundle pacing (HBP), biventricular pacing (BiVP), and RVP for advanced AVB in patients with normal or mildly reduced EF.

METHODS AND RESULTS

MEDLINE, Embase, Cochrane CENTRAL, ClinicalTrials.gov, Scopus, and Web of Science were searched. Outcomes were all-cause death, heart failure hospitalizations (HFH), EF, left ventricular volumes, 6-minute walk test, and QRS duration. HBP or BiVP was compared with RVP. Subsequently, network meta-analysis compared the three pacing options. Our protocol was registered in PROSPERO (CRD42018094132). Six studies compared BiVP and RVP (704 vs 614 patients) and four compared HBP and RVP (463 vs 568 patients). Follow-up was 6 months to 5 years. There was significantly lower mortality and HFH with HBP or BiVP as compared with RVP (odds ratio [OR], 0.66, [0.51-0.85], P = .002; OR, 0.61 [0.45-0.82], P < .001, respectively]. HBP or BiVP also showed significant increase in EF and decrease in QRS duration (mean difference [MD], 5.27 [3.86-6.69], P < .001; MD -42.2 [-51.2 to -33.3], P < .001, respectively). In network meta-analysis, HBP and BiVP were associated with significantly improved survival compared to RVP, with surface under the cumulative ranking curve (SUCRA) probability of 79.4%, 69.4%, and 1.2% for HBP, BiVP, and RVP, respectively. For HFH, SUCRA probability was 91.5%, 57.2%, and 1.3%, respectively.

CONCLUSION

HBP or BiVP were the superior strategies to reduce all-cause death and HFH for advanced AVB with normal or mildly reduced EF, with no significant difference between BiVP and HBP.

Health Care Costs After Cardiac Arrest in the United States

BACKGROUND

This study was designed to estimate the costs of index hospitalizations after cardiac arrest in the United States.

METHODS AND RESULTS

We used the US Nationwide Inpatient Sample (2003-2012) to identify patients with cardiac arrest. Log transformation of inflation-adjusted cost was determined for care to patient outcomes. Overall, an estimated 1 387 396 patients were hospitalized after cardiac arrest. The mean age of the cohort was 66 years, 45% were women, and the majority were white. Inpatient procedures included coronary angiography (15%), percutaneous coronary intervention (7%), intra-aortic balloon pump (4.4%), therapeutic hypothermia (1.1%), and mechanical circulatory support (0.1%). The rates of therapeutic hypothermia increased from zero in 2003 to 2.7% in 2012 (P<0.001). Both hospital charges and inflation-adjusted cost increased linearly over time. In a multivariate analysis, predictors of inflation-adjusted cost included large hospital size, urban teaching hospital, and length of stay. Among comorbidities, atrial fibrillation or fluid and electrolytes imbalance was most associated with cost. Among selected interventions, the cost was significantly increased with automatic implantable cardioverter defibrillators (odds ratio, 1.83; P<0.001), intra-aortic balloon pump (odds ratio, 1.50; P<0.001), hypothermia (odds ratio, 1.28; P<0.001), and extracorporeal membrane oxygenation (odds ratio, 2.38; P<0.001).

CONCLUSIONS

In the period between 2003 and 2012, postcardiac arrest hospitalizations resulted in a steady rise in associated health care cost, likely related to increased length of stay, medical procedures, and systems of care. Although targeted cost containment for postarrest interventions may reduce the finance burden, there is an increasing need for funding research into prediction and prevention of cardiac arrest, which offers greater societal benefit.

Rationale and Design of the CONCERT-HF Trial (Combination of Mesenchymal and c-kit+ Cardiac Stem Cells As Regenerative Therapy for Heart Failure)

RATIONALE

Autologous bone marrow mesenchymal stem cells (MSCs) and c-kit⁺ cardiac progenitor cells (CPCs) are 2 promising cell types being evaluated for patients with heart failure (HF) secondary to ischemic cardiomyopathy. No information is available in humans about the relative efficacy of MSCs and CPCs and whether their combination is more efficacious than either cell type alone.

OBJECTIVE

CONCERT-HF (Combination of Mesenchymal and c-kit⁺ Cardiac Stem Cells As Regenerative Therapy for Heart Failure) is a phase II trial aimed at elucidating these issues by assessing the feasibility, safety, and efficacy of transendocardial administration of autologous MSCs and CPCs, alone and in combination, in patients with HF caused by chronic ischemic cardiomyopathy (coronary artery disease and old myocardial infarction).

METHODS AND RESULTS

Using a randomized, double-blinded, placebo-controlled, multicenter, multitreatment, and adaptive design, CONCERT-HF examines whether administration of MSCs alone, CPCs alone, or MSCs+CPCs in this population alleviates left ventricular remodeling and dysfunction, reduces scar size, improves quality of life, or augments functional capacity. The 4-arm design enables comparisons of MSCs alone with CPCs alone and with their combination. CONCERT-HF consists of 162 patients, 18 in a safety lead-in phase (stage 1) and 144 in the main trial (stage 2). Stage 1 is complete, and stage 2 is currently randomizing patients from 7 centers across the United States.

CONCLUSIONS

CONCERT-HF will provide important insights into the potential therapeutic utility of MSCs and CPCs, given alone and in combination, for patients with HF secondary to ischemic cardiomyopathy.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02501811.

Dose Comparison Study of Allogeneic Mesenchymal Stem Cells in Patients With Ischemic Cardiomyopathy (The TRIDENT Study)

RATIONALE

Cell dose and concentration play crucial roles in phenotypic responses to cell-based therapy for heart failure.

OBJECTIVE

To compare the safety and efficacy of 2 doses of allogeneic bone marrow-derived human mesenchymal stem cells identically delivered in patients with ischemic cardiomyopathy.

METHODS AND RESULTS

Thirty patients with ischemic cardiomyopathy received in a blinded manner either 20 million (n=15) or 100 million (n=15) allogeneic human mesenchymal stem cells via transendocardial injection (0.5 cc per injection × 10 injections per patient). Patients were followed for 12 months for safety and efficacy end points. There were no treatment-emergent serious adverse events at 30 days or treatment-related serious adverse events at 12 months. The Major Adverse Cardiac Event rate was 20.0% (95% confidence interval [CI], 6.9% to 50.0%) in 20 million and 13.3% (95% CI, 3.5% to 43.6%) in 100 million (P=0.58). Worsening heart failure rehospitalization was 20.0% (95% CI, 6.9% to 50.0%) in 20 million and 7.1% (95% CI, 1.0% to 40.9%) in 100 million (P=0.27). Whereas scar size reduced to a similar degree in both groups: 20 million by -6.4 g (interquartile range, -13.5 to -3.4 g; P=0.001) and 100 million by -6.1 g (interquartile range, -8.1 to -4.6 g; P=0.0002), the ejection fraction improved only with 100 million by 3.7 U (interquartile range, 1.1 to 6.1; P=0.04). New York Heart Association class improved at 12 months in 35.7% (95% CI, 12.7% to 64.9%) in 20 million and 42.9% (95% CI, 17.7% to 71.1%) in 100 million. Importantly, proBNP (pro-brain natriuretic peptide) increased at 12 months in 20 million by 0.32 log pg/mL (95% CI, 0.02 to 0.62; P=0.039), but not in 100 million (-0.07 log pg/mL; 95% CI, -0.36 to 0.23; P=0.65; between group P=0.07).

CONCLUSIONS

Although both cell doses reduced scar size, only the 100 million dose increased ejection fraction. This study highlights the crucial role of cell dose in the responses to cell therapy. Determining optimal dose and delivery is essential to advance the field, decipher mechanism(s) of action and enhance planning of pivotal Phase III trials.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02013674.

Effects of Transendocardial Stem Cell Injection on Ventricular Proarrhythmia in Patients with Ischemic Cardiomyopathy: Results from the POSEIDON and TAC-HFT Trials

Transendocardial stem cell injection in patients with ischemic cardiomyopathy (ICM) improves left ventricular function and structure but has ill-defined effects on ventricular arrhythmias. We hypothesized that mesenchymal stem cell (MSC) implantation is not proarrhythmic. Post hoc analyses were performed on ambulatory ECGs collected from the POSEIDON and TAC-HFT trials. Eighty-eight subjects (mean age 61 ± 10 years) with ICM (mean EF 32.2% ± 9.8%) received treatment with MSC (n = 48), Placebo (n = 21), or bone marrow mononuclear cells (BMC) (n = 19). Heart rate variability (HRV) and ventricular ectopy (VE) were evaluated over 12 months. VE did not change in any group following MSC implantation. However, in patients with ≥ 1 VE run (defined as ≥ 3 consecutive premature ventricular complexes in 24 hours) at baseline, there was a decrease in VE runs at 12 months in the MSC group (p = .01), but not in the placebo group (p = .07; intergroup comparison: p = .18). In a subset of the MSC group, HRV measures of standard deviation of normal intervals was 75 ± 30 msec at baseline and increased to 87 ± 32 msec (p =.02) at 12 months, and root mean square of intervals between successive complexes was 36 ± 30 msec and increased to 58.2 ± 50 msec (p = .01) at 12 months. In patients receiving MSCs, there was no evidence for ventricular proarrhythmia, manifested by sustained or nonsustained ventricular ectopy or worsened HRV. Signals of improvement in ventricular arrhythmias and HRV in the MSC group suggest a need for further studies of the antiarrhythmic potential of MSCs. Stem Cells Translational Medicine 2017;6:1366-1372.

Gender, Race, and Health Insurance Status in Patients Undergoing Catheter Ablation for Atrial Fibrillation

Catheter ablation for atrial fibrillation (AF) has emerged as a popular procedure. The purpose of this study was to examine whether there exist differences or disparities in ablation utilization across gender, socioeconomic class, insurance, or race. Using the Nationwide Inpatient Sample (2000 to 2012), we identified adults hospitalized with a principal diagnosis of AF by ICD 9 code 427.31 who had catheter ablation (ICD 9 code-37.34). We stratified patients by race, insurance status, age, gender, and hospital characteristics. A hierarchical multivariate mixed-effect model was created to identify the independent predictors of AF ablation. Among an estimated total of 3,508,122 patients (extrapolated from 20% Nationwide Inpatient Sample) hospitalized with a diagnosis of AF in the United States from the year 2000 to 2012, 102,469 patients (2.9%) underwent catheter ablations. The number of ablations was increased by 940%, from 1,439 in 2000 to 15,090 in 2012. There were significant differences according to gender, race, and health insurance status, which persisted even after adjustment for other risk factors. Female gender (0.83 [95% CI 0.79 to 0.87; p <0.001]), black (0.49 [95% CI 0.44 to 0.55; p <0.001]), and Hispanic race (0.64 [95% CI 0.56 to 0.72; p <0.001]) were associated with lower likelihoods of undergoing an AF ablation. Medicare (0.93, 0.88 to 0.98, <0.001) or Medicaid (0.67, 0.59 to 0.76, <0.001) coverage and uninsured patients (0.55, 0.49 to 0.62, <0.001) also had lower rates of AF ablation compared to patients with private insurance. In conclusion we found differences in utilization of catheter ablation for AF based on gender, race, and insurance status that persisted over time.

Gender, Racial, and Health Insurance Differences in the Trend of Implantable Cardioverter-Defibrillator (ICD) Utilization: A United States Experience Over the Last Decade

Prior studies have highlighted disparities in cardiac lifesaving procedure utilization, particularly among women and in minorities. Although there has been a significant increase in implantable cardioverter-defibrillator (ICD) insertion, socioeconomic disparities still exist in the trend of ICD utilization. With the use of the Nationwide Inpatient Sample from 2003 through 2011, we identified subjects with ICD insertion (procedure code 37.94) and cardiac resynchronization defibrillator (procedure code 00.50, 00.51) as codified by the International Classification of Diseases, Ninth Revision, Clinical Modification. Overall, 1 020 076 ICDs were implanted in the United States from 2003 to 2011. We observed an initial increase in ICD utilization by 51%, from 95 062 in 2003 to 143 262 in 2006, followed by a more recent decline. The majority of ICDs were implanted in men age ≥65 years. Implantation of ICDs was 2.5× more common in men than in women (402 per million vs 163 per million). Approximately 95% of the ICDs were implanted in insured patients, and 5% were used in the uninsured population. There has been a significant increase in ICD implantation in blacks, from 162 per million in 2003 to 291 per million in 2011. We found a significant difference in the volume of ICD implants between the insured and the uninsured patient populations. Racial disparities have narrowed significantly in comparison with those noted in earlier studies and are now more reflective of the population demographics at large. On the other hand, significant gender disparities continue to exist.

Abstract 282: Clinical Outcomes and In-hospital Cost of Care After Resuscitation From Cardiac Arrest: Insights From the US National Inpatient Sample 2008 to 2012

Introduction: Cardiac arrest remains a major public health problem that requires study with a focus on improved outcomes and cost-effective care. The aim of this study was to examine clinical outcomes and health care cost associated with hospitalization after cardiac arrest in the United States from 2008-2012.

Methods: Clinical outcomes, including mortality and health care cost, were examined using the US National Inpatient Sample from 2008 to 2012. The International Classification of Diseases, 9th Edition, code 427.5 was used to identify patients with cardiac arrest. Total health care cost was the primary outcome of interest. We used student-t and x2 tests for comparisons. Univariable and multivariable analyses were used to evaluate the effects of clinical characteristics and medical procedures on health care cost for patients after resuscitation from cardiac arrest.

Results: An estimated 751, 873 patients were admitted with the diagnosis of cardiac arrest. The mean age of the study population was 67 years, 45% were female, and 68% were Caucasians. Hypertension and fluid/electrolyte disorders were observed in approximately 46% of the population. Patients with > 2 comorbidities increased overtime (2008: 51% vs. 2012: 59%, p <0.001). The inpatient procedures performed on the study group were intubation (51%), coronary angiography (16%), and PTCA (8%). The rates of therapeutic hypothermia increased steadily overtime (2008: 0.6% vs. 2012: 2.8%, p <0.001). The mean in-hospital mortality was 60%, with a mean length of stay of 9 days. In a multivariable analysis, age was negatively associated with cost (Estimate: -692, CI -708 to -550, p < 0.001). Factors that were associated with increased health cost were increasing length of stay, coronary angiography or PTCA, and therapeutic hypothermia. Adjusting for clinical variables, the health care cost increased overtime (Figure).

Conclusion: This study found an improved post-resuscitation mortality rates compared to prior decades. Further, this survival was associated with a significant steady increase in post-arrest hospital cost, likely related to increased length of stay, medical procedures, and systems of care. The figures do not include additional post-hospital costs that continue to accrue over time.

Ten advances defining sudden cardiac death

Recent advances in the field of sudden cardiac death (SCD) include the recognition that 50% of SCD occurs as initial presentation of any heart disease and that many of these individuals may have been considered to be low risk. The presenting dysrhythmia in patients with cardiac arrests has changed over time such that pulseless electrical activity and asystole is more frequently encountered as compared with ventricular tachyarrhythmias. While the use of implantable defibrillators has been a tremendous advance in patients at risk for ventricular tachyarrhythmias, the use of automatic external defibrillators and wearable defibrillators is a recent advance that allows for potential SCD prevention in more patients. Finally, the area of medical genetics is an evolving discipline, which may enable clinicians to better individualize therapy for patients with genetic predispositions to cardiac dysrhythmias.

Contemporary trends of hospitalization for atrial fibrillation in the United States, 2000 through 2010: implications for healthcare planning

BACKGROUND

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The associated morbidity and mortality make AF a major public health burden. Hospitalizations account for the majority of the economic cost burden associated with AF. The main objective of this study is to examine the trends of AF-related hospitalizations in the United States and to compare patient characteristics, outcomes, and comorbid diagnoses.

METHODS AND RESULTS

With the use of the Nationwide Inpatient Sample from 2000 through 2010, we identified AF-related hospitalizations using International Classification of Diseases, 9th Revision, Clinical Modification code 427.31 as the principal discharge diagnosis. Overall AF hospitalizations increased by 23% from 2000 to 2010, particularly in patients ≥65 years of age. The most frequent coexisting conditions were hypertension (60.0%), diabetes mellitus (21.5%), and chronic pulmonary disease (20.0%). Overall in-hospital mortality was 1%. The mortality rate was highest in the group of patients ≥80 years of age (1.9%) and in the group of patients with concomitant heart failure (8.2%). In-hospital mortality rate decreased significantly from 1.2% in 2000 to 0.9% in 2010 (29.2% decrease; P<0.001). Although there was no significant change in mean length of stay, mean cost of AF hospitalization increased significantly from $6410 in 2001 to $8439 in 2010 (24.0% increase; P<0.001).

CONCLUSIONS

Hospitalization rates for AF have increased exponentially among US adults from 2000 to 2010. The proportion of comorbid chronic diseases has also increased significantly. The last decade has witnessed an overall decline in hospital mortality; however, the hospitalization cost has significantly increased.

New-onset atrial fibrillation after aortic valve replacement: comparison of transfemoral, transapical, transaortic, and surgical approaches

OBJECTIVES

This study sought to determine the incidence of new-onset atrial fibrillation (AF) associated with different methods of isolated aortic valve replacement (AVR)-transfemoral (TF), transapical (TA), and transaortic (TAo) catheter-based valve replacement and conventional surgical approaches.

BACKGROUND

The relative incidences of AF associated with the various access routes for AVR have not been well characterized.

METHODS

In this single-center, retrospective cohort study, we evaluated a total of 231 consecutive patients who underwent AVR for degenerative aortic stenosis (AS) between March 2010 and September 2012. Patients with a history of paroxysmal, persistent, or chronic AF, with bicuspid aortic valves, and patients who died within 48 h after AVR were excluded. A total of 123 patients (53% of total group) qualified for inclusion. Data on documented episodes of new-onset AF, along with all clinical, echocardiographic, procedural, and 30-day follow-up data, were collated.

RESULTS

AF occurred in 52 patients (42.3%). AF incidence varied according to the procedural method. AF occurred in 60% of patients who underwent surgical AVR (SAVR), in 53% after TA-TAVR, in 33% after TAo-TAVR cases, and 14% after TF-TAVR. The episodes occurred at a median time interval of 53 (25th to 75th percentile, 41 to 87) h after completion of the procedure. Procedures without pericardiotomy had an 82% risk reduction of AF compared with those with pericardiotomy (adjusted odds ratio: 0.18; 95% confidence interval: 0.05 to 0.59).

CONCLUSIONS

AF was a common complication of AVR with a cumulative incidence of >40% in elderly patients with degenerative AS who underwent either SAVR or TAVR. AF was most common with SAVR and least common with TF-TAVR. Procedures without pericardiotomy were associated with a lower incidence of AF.

Wearable defibrillators in uninsured patients with newly diagnosed cardiomyopathy or recent revascularization in a community medical center

BACKGROUND

The wearable defibrillator (WD) can prevent sudden death in patients who are not candidates for an implantable cardioverter-defibrillator (ICD).

OBJECTIVES

We studied outcomes of uninsured patients prescribed a WD.

METHODS

A consecutive series of patients were prescribed a WD because of a new onset cardiomyopathy or coronary artery revascularization with a predischarge ejection fraction (EF) ≤35%. Patients were followed up for WD compliance, events, EF changes, and subsequent ICD implants.

RESULTS

Among 134 patients with cardiomyopathy diagnosed at a mean age of 52.7 ± 11.6 years and with a mean EF of 22.5% ± 7.3%, 125 patients (93%) were newly diagnosed with cardiomyopathy. There were 77 patients (57%) with nonischemic cardiomyopathy and 57 (43%) with ischemic cardiomyopathy. Patients wore the WD for a mean of 14.1 ± 8.1 hours per day for 72 ± 55 days. There were no shocks or detected arrhythmias. Forty-eight patients (35%) were lost to follow-up. No ICDs were implanted in 33 (38%) of the other 86 patients, whose EF improved to above 35%. Of the 53 patients with persistent EF ≤35%, 44 patients (83%) received an ICD. However, 12 (27%) of these 44 patients had ICD implant before 90 days after the index event.

CONCLUSION

There was a high lost to follow-up rate in an uninsured population. There were no sustained ventricular tachyarrhythmia events. Wearable defibrillator utilization prevented ICD implant in the subgroup of patients with EF improvement, although there were still premature implants based on Centers for Medicare and Medicaid Guideline waiting periods.