Minneapolis, United States
Minneapolis, United States

Time filter

Source Type

Maron B.J.,Minneapolis Heart Institute Foundation | Ommen S.R.,Mayo Medical School | Semsarian C.,University of Sydney | Spirito P.,Ente Ospedaliero Ospedali Galliera | Olivotto I.,University of Florence
Journal of the American College of Cardiology | Year: 2014

Hypertrophic cardiomyopathy (HCM) is a common inherited heart disease with diverse phenotypic and genetic expression, clinical presentation, and natural history. HCM has been recognized for 55 years, but recently substantial advances in diagnosis and treatment options have evolved, as well as increased recognition of the disease in clinical practice. Nevertheless, most genetically and clinically affected individuals probably remain undiagnosed, largely free from disease-related complications, although HCM may progress along 1 or more of its major disease pathways (i.e., arrhythmic sudden death risk; progressive heart failure [HF] due to dynamic left ventricular [LV] outflow obstruction or due to systolic dysfunction in the absence of obstruction; or atrial fibrillation with risk of stroke). Effective treatments are available for each adverse HCM complication, including implantable cardioverter-defibrillators (ICDs) for sudden death prevention, heart transplantation for end-stage failure, surgical myectomy (or selectively, alcohol septal ablation) to alleviate HF symptoms by abolishing outflow obstruction, and catheter-based procedures to control atrial fibrillation. These and other strategies have now resulted in a low disease-related mortality rate of <1%/year. Therefore, HCM has emerged from an era of misunderstanding, stigma, and pessimism, experiencing vast changes in its clinical profile, and acquiring an effective and diverse management armamentarium. These advances have changed its natural history, with prevention of sudden death and reversal of HF, thereby restoring quality of life with extended (if not normal) longevity for most patients, and transforming HCM into a contemporary treatable cardiovascular disease. © 2014 by the American College of Cardiology Foundation.


Maron B.J.,Minneapolis Heart Institute Foundation | Maron M.S.,Hypertrophic Cardiomyopathy Center | Semsarian C.,University of Sydney | Semsarian C.,Royal Prince Alfred Hospital
Journal of the American College of Cardiology | Year: 2012

Hypertrophic cardiomyopathy (HCM) is the most common familial heart disease with vast genetic heterogeneity, demonstrated over the past 20 years. Mutations in 11 or more genes encoding proteins of the cardiac sarcomere (>1,400 variants) are responsible for (or associated with) HCM. Explosive progress achieved in understanding the rapidly evolving science underlying HCM genomics has resulted in fee-for-service testing, making genetic information widely available. The power of HCM mutational analysis, albeit a more limited role than initially envisioned, lies most prominently in screening family members at risk for developing disease and excluding unaffected relatives, which is information not achievable otherwise. Genetic testing also allows expansion of the broad HCM disease spectrum and diagnosis of HCM phenocopies with different natural history and treatment options, but is not a reliable strategy for predicting prognosis. Interfacing a heterogeneous disease such as HCM with the vast genetic variability of the human genome, and high frequency of novel mutations, has created unforeseen difficulties in translating complex science (and language) into the clinical arena. Indeed, proband diagnostic testing is often expressed on a probabilistic scale, which is frequently incompatible with clinical decision making. Major challenges rest with making reliable distinctions between pathogenic mutations and benign variants, and those judged to be of uncertain significance. Genotyping in HCM can be a powerful tool for family screening and diagnosis. However, wider adoption and future success of genetic testing in the practicing cardiovascular community depends on a standardized approach to mutation interpretation, and bridging the communication gap between basic scientists and clinicians. © 2012 American College of Cardiology Foundation.


Maron B.J.,Minneapolis Heart Institute Foundation | Maron B.J.,Tufts Medical Center | Maron M.S.,Minneapolis Heart Institute Foundation | Maron M.S.,Tufts Medical Center
The Lancet | Year: 2013

Hypertrophic cardiomyopathy is a common inherited cardiovascular disease present in one in 500 of the general population. It is caused by more than 1400 mutations in 11 or more genes encoding proteins of the cardiac sarcomere. Although hypertrophic cardiomyopathy is the most frequent cause of sudden death in young people (including trained athletes), and can lead to functional disability from heart failure and stroke, the majority of affected individuals probably remain undiagnosed and many do not experience greatly reduced life expectancy or substantial symptoms. Clinical diagnosis is based on otherwise unexplained left-ventricular hypertrophy identified by echocardiography or cardiovascular MRI. While presenting with a heterogeneous clinical profile and complex pathophysiology, effective treatment strategies are available, including implantable defibrillators to prevent sudden death, drugs and surgical myectomy (or, alternatively, alcohol septal ablation) for relief of outflow obstruction and symptoms of heart failure, and pharmacological strategies (and possibly radiofrequency ablation) to control atrial fibrillation and prevent embolic stroke. A subgroup of patients with genetic mutations but without left-ventricular hypertrophy has emerged, with unresolved natural history. Now, after more than 50 years, hypertrophic cardiomyopathy has been transformed from a rare and largely untreatable disorder to a common genetic disease with management strategies that permit realistic aspirations for restored quality of life and advanced longevity.


Hauser R.G.,Minneapolis Heart Institute Foundation | McGriff D.,Minneapolis Heart Institute Foundation | Retel L.K.,Minneapolis Heart Institute Foundation
Heart Rhythm | Year: 2012

BACKGROUND: The Riata family of implantable cardioverter-defibrillator leads (St Jude Medical, Sylmar, CA) appears prone to a unique failure mechanism whereby the conductor cables wear through the silicone insulation from inside-out and are seen outside the lead body (externalized conductors). OBJECTIVE: To assess the extent of Riata lead damage associated with inside-out insulation defects and their clinical consequences. METHODS: In September 2011, we searched the U.S. Food and Drug Administration's Manufacturers and User Defined Experience medical device database for reports describing Riata lead failures that had been analyzed by the manufacturer. RESULTS: The Manufacturers and User Defined Experience search identified 105 leads that had inside-out insulation defects. Eight-French single-coil Riata leads accounted for a higher-than-expected proportion (25.7%) of the leads with this defect. A total of 226 insulation defects were found in the 105 leads (2.2 defects per lead), including 143 inside-out defects (1.4 defects per lead). The most common location of insulation defects was distal to the proximal coil (n = 108). Twenty-eight leads (26.7%) had inside-out insulation defects underneath the shocking coils. Of 43 leads whose cables were assessed for the integrity of the ethylene-tetrafluoroethylene cable coating, 22 (51.2%) were found to be abraded, exposing the conductor surfaces. On X-ray radiography or fluoroscopy, 7 leads were found to have externalized cables; 2 of these leads had no electrical abnormalities, while 4 exhibited noise or increased impedance. Inappropriate shocks were experienced by 31 of the 105 patients (29.5%). CONCLUSION: Riata leads that have inside-out insulation defects often have multiple defects, including additional inside-out abrasions along the body of the lead and beneath the shocking coils. Eight-French single-coil Riata models may be more prone to externalized cables than are dual-coil and 7-F designs. Externalized cables are but one manifestation of interior insulation damage. Our findings question the durability of the ethylene-tetrafluoroethylene cable coating on exposed cables. © 2012 Heart Rhythm Society.


Hauser R.G.,Minneapolis Heart Institute Foundation
Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology | Year: 2013

The purpose of this study was to determine if Optim™, a unique copolymer of silicone and polyurethane, protects Riata ST Optim and Durata implantable cardioverter-defibrillator (ICD) leads (SJM, St Jude Medical Inc., Sylmar, CA, USA) from abrasions that cause lead failure. We searched the US Food and Drug Administration's (FDA's) Manufacturers and User Device Experience (MAUDE) database on 13 April 2012 using the simple search terms 'Riata ST Optim™ abrasion analysis' and 'Durata abrasion analysis'. Lead implant time was estimated by subtracting 3 months from the reported lead age. The MAUDE search returned 15 reports for Riata ST Optim™ and 37 reports for Durata leads, which were submitted by SJM based on its analyses of returned leads for clinical events that occurred between December 2007 and January 2012. Riata ST Optim™ leads had been implanted 29.1 ± 11.7 months. Eight of 15 leads had can abrasions and three abrasions were caused by friction with another device, most likely another lead. Four of these abrasions resulted in high-voltage failures and one death. One failure was caused by an internal insulation defect. Durata leads had been implanted 22.2 ± 10.6 months. Twelve Durata leads had can abrasions, and six leads had abrasions caused by friction with another device. Of these 18 can and other device abrasions, 13 (72%) had electrical abnormalities. Low impedances identified three internal insulation abrasions. Riata ST Optim™ and Durata ICD leads have failed due to insulation abrasions. Optim™ did not prevent these abrasions, which developed ≤ 4 years after implant. Studies are needed to determine the incidence of these failures and their clinical implications.


Sharkey S.W.,Minneapolis Heart Institute Foundation
Heart Failure Clinics | Year: 2013

This article provides a comprehensive review of the clinical features of takotsubo (stress) cardiomyopathy. The author discusses key features that distinguish this cardiomyopathy from acute coronary syndrome. This review includes detail of characteristic findings on electrocardiogram, biochemical testing, and cardiac imaging, as well as complications including congestive heart failure, arrhythmia, ventricular thrombi, and left ventricular outflow obstruction. The review concludes with a discussion of the proper treatment, long-term survival, and proposed pathophysiology. © 2013 Elsevier Inc.


Maron B.J.,Minneapolis Heart Institute Foundation | Estes III N.A.M.,Tufts University
New England Journal of Medicine | Year: 2010

In the past decade, the general public and the medical community have become more aware of commotio cordis as an important cause of sudden death. Commotio cordis occurs in otherwise healthy and active young people, typically during recreational and competitive sports but in some cases even during normal daily activities. A variety of experimental models indicate that if delivered at a particular moment in the cardiac cycle, even innocent-appearing precordial blows can trigger ventricular fibrillation and result in fatal commotio cordis events. Further efforts are needed to prevent these largely avoidable deaths by providing more education, better-designed athletic equipment (e.g., effective chest-wall protectors), and wider access to AEDs at organized athletic events. These strategies should result in a safer sports environment for our youth. Copyright © 2010 Massachusetts Medical Society. All rights reserved.


Maron B.J.,Minneapolis Heart Institute Foundation
Heart rhythm : the official journal of the Heart Rhythm Society | Year: 2013

Commotio cordis events due to precordial blows triggering ventricular fibrillation are a cause of sudden death (SD) during sports and also daily activities. Despite the absence of structural cardiac abnormalities, these events have been considered predominantly fatal with low survival rates. To determine whether expected mortality rates for commotio cordis have changed over time, associated with greater public visibility. US Commotio Cordis Registry was accessed to tabulate frequency of reported SD or resuscitated cardiac arrest over 4 decades. At their commotio cordis event, 216 study patients were 0.2-51 years old (mean age 15±9 years); 95% were males. Death occurred in 156 individuals (72%), while the other 60 (28%) survived. Proportion of survivors increased steadily with concomitant decrease in fatal events. For the initial years (1970-1993), 6 of 59 cases survived (10%), while during 1994-2012, 54 of 157 (34%) survived (P = .001). The most recent 6 years, survival from commotio cordis was 31 of 53 (58%), with survivor and nonsurvivor curves ultimately crossing. Higher survival rates were associated with more prompt resuscitation (40%<3 minutes vs 5%>3 minutes; P<.001) and participation in competitive sports (39%; P<.001), but with lower rates in African Americans (1 of 24; 4%) than in whites (54 of 166; 33%; P = .004). Independent predictors of mortality were black race (P = .045) and participation in noncompetitive sports (P = .002), with an on-site automated external defibrillator use protective against SD (P = .01). Survival from commotio cordis has increased, likely owing to more rapid response times and access to defibrillation, as well as greater public awareness of this condition. Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.


Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death (SCD) in young people, including trained athletes. It is now 30 years since the introduction of implantable cardioverter-defibrillators (ICDs) to clinical cardiovascular practice and coronary artery disease, and now device therapy represents the most significant therapeutic innovation and the only definitive strategy for prolonging the life of HCM patients. ICDs have proved effective in preventing SCD in young HCM patients with appropriate intervention rates of 11% for secondary and 4% for primary prevention, despite massive left ventricular (LV) hypertrophy, LV outflow obstruction, diastolic dysfunction or microvascular ischemia. Targeting candidates for prophylactic ICD therapy can be complex, compounded by the unpredictability of the arrhythmogenic substrate, the absence of a dominant risk factor, and difficulty in assembling randomized trials. However, a single major risk factor is often sufficient to justify an ICD, although additional markers and other disease features can resolve ambiguous decision-making. Nevertheless, the absence of all risk factors does not convey absolute immunity to SCD. The current risk factor algorithm, when combined with a measure of individual physician judgment (and patient autonomy considerations), is an effective guide to identifying high-risk HCM patients. ICDs have altered the natural history of HCM for many patients and provided an opportunity to achieve many decades of productive life, and the potential for normal or near-normal longevity. Indeed, prevention of SCD has now become a new paradigm in the management of HCM.


Maron B.J.,Minneapolis Heart Institute Foundation | Haas T.S.,Minneapolis Heart Institute Foundation | Murphy C.J.,Minneapolis Heart Institute Foundation | Ahluwalia A.,Minneapolis Heart Institute Foundation | Rutten-Ramos S.,Minneapolis Heart Institute Foundation
Journal of the American College of Cardiology | Year: 2014

Objectives The goal of this study was to reliably define the incidence and causes of sudden death in college student-athletes. Background The frequency with which cardiovascular-related sudden death occurs in competitive athletes importantly influences considerations for pre-participation screening strategies. Methods We assessed databases (including autopsy reports) from both the U.S. National Registry of Sudden Death in Athletes and the National Collegiate Athletic Association (2002 to 2011). Results Over the 10-year study period, 182 sudden deaths occurred (age 20 ± 1.7 years; 85% male; 64% white), 52 resulting from suicide (n = 31) or drug abuse (n = 21) and 64 probably or likely attributable to cardiovascular causes (6/year). Of these 64 athletes, 47 had a confirmed post-mortem diagnosis; the most common were hypertrophic cardiomyopathy in 21 and congenital coronary anomalies in 8. The 4,052,369 athlete participations (in 30 sports over 10 years) incurred mortality risks as follows: suicide and drugs combined, 1.3/100,000 athlete participation-years (5 deaths/year); and documented cardiovascular disease, 1.2/100,000 athlete participation-years (4 deaths/year). Notably, cardiovascular deaths were 5-fold more common in African-American athletes than in white athletes (3.8 vs. 0.7/100,000 athlete participation-years; p < 0.01) but did not differ from the general population of the same age and race (p = 0.6). Conclusions In college student-athletes, risk of sudden death due to cardiovascular disease is relatively low, with mortality rates similar to suicide and drug abuse, but less than expected in the general population, although highest in African-American athletes. A substantial minority of confirmed cardiovascular deaths would not likely have been reliably detected by pre-participation screening with 12-lead electrocardiograms. © 2014 by the American College of Cardiology Foundation.

Loading Minneapolis Heart Institute Foundation collaborators
Loading Minneapolis Heart Institute Foundation collaborators