Comparison of risk profiles between survivors and victims of sudden cardiac death from an acute coronary event

Characteristics of women with ischemic sudden cardiac death

BACKGROUND

Sudden cardiac death (SCD) is a significant mode of death causing 15-20% of all deaths in high-income countries. Coronary artery disease (CAD) is the most common cause of SCD in both sexes, and SCD is often the first manifestation of underlying CAD in women. This case-control study aimed to determine the factors associated with SCD due to CAD in women.

METHODS

The study group consisted of women with CAD-related SCD (N = 888) derived from the Fingesture study conducted in Northern Finland from 1998 to 2017. All SCDs underwent medicolegal autopsy. The control group consisted of women with angiographically verified CAD without SCD occurring during the 5-year-follow-up (N = 610). To compare these groups, we used medical records, autopsy findings, echocardiograms, and electrocardiograms (ECGs).

RESULTS

Subjects with SCD were older (73.2 ± 11.3 vs. 68.8 ± 8.0, p < 0.001) and were more likely to be smokers or ex-smokers (37.1% vs. 27.6%, p = 0.045) compared to control patients. The proportion of subjects with prior myocardial infarction (MI) was higher in controls (46.9% vs. 41.4% in SCD subjects, p = 0.037), but in contrast, SCD subjects were more likely to have underlying silent MI (25.6% vs. 2.4% in CAD controls, p < 0.001). Left ventricular hypertrophy (LVH) was more common finding in SCD subjects (70.9% vs. 55.1% in controls, p < 0.001). Various electrocardiographic abnormalities were more common in subjects with SCD, including higher heart rate, atrial fibrillation, prolonged QTc interval, wide or fragmented QRS complex and early repolarization. The prevalence of Q waves and T inversions did not differ between the groups.

CONCLUSIONS

Underlying LVH and previous MI with myocardial scarring are common and often undiagnosed in women with CAD-related SCD. These results suggest that untreated CAD with concomitant myocardial disease is an important factor in SCD in women.

The Lancet Commission to reduce the global burden of sudden cardiac death: a call for multidisciplinary action

Despite major advancements in cardiovascular medicine, sudden cardiac death (SCD) continues to be an enormous medical and societal challenge, claiming millions of lives every year. Efforts to prevent SCD are hampered by imperfect risk prediction and inadequate solutions to specifically address arrhythmogenesis. Although resuscitation strategies have witnessed substantial evolution, there is a need to strengthen the organisation of community interventions and emergency medical systems across varied locations and health-care structures. With all the technological and medical advances of the 21st century, the fact that survival from sudden cardiac arrest (SCA) remains lower than 10% in most parts of the world is unacceptable. Recognising this urgent need, the Lancet Commission on SCD was constituted, bringing together 30 international experts in varied disciplines. Consistent progress in tackling SCD will require a completely revamped approach to SCD prevention, with wide-sweeping policy changes that will empower the development of both governmental and community-based programmes to maximise survival from SCA, and to comprehensively attend to survivors and decedents' families after the event. International collaborative efforts that maximally leverage and connect the expertise of various research organisations will need to be prioritised to properly address identified gaps. The Commission places substantial emphasis on the need to develop a multidisciplinary strategy that encompasses all aspects of SCD prevention and treatment. The Commission provides a critical assessment of the current scientific efforts in the field, and puts forth key recommendations to challenge, activate, and intensify efforts by both the scientific and global community with new directions, research, and innovation to reduce the burden of SCD worldwide.

Plaque histology and myocardial disease in sudden coronary death: the Fingesture study

AIMS

At least 50% of deaths due to coronary artery disease (CAD) are sudden cardiac deaths (SCDs), but the role of acute plaque complications on the incidence of sudden death in CAD is somewhat unclear. The present study aimed to investigate plaque histology and concomitant myocardial disease in sudden coronary death.

METHODS AND RESULTS

The study population is derived from the Fingesture study, which has collected data from 5869 consecutive autopsy-verified SCD victims in Northern Finland (population ≈600 000) between 1998 and 2017. In this substudy, histological examination of culprit lesions was performed in 600 SCD victims whose death was due to CAD. Determination of the cause of death was based on the combination of medical records, police reports, and autopsy data. Plaque histology was classified as either (i) plaque rupture or erosion, (ii) intraplaque haemorrhage, or (iii) stable plaque. The mean age of the study subjects was 64.9 ± 11.2 years, and 82% were male. Twenty-four per cent had plaque rupture or plaque erosion, 24% had an intraplaque haemorrhage, and 52% had a stable plaque. Myocardial hypertrophy was present in 78% and myocardial fibrosis in 93% of victims. The presence of myocardial hypertrophy or fibrosis was not associated with specific plaque histology.

CONCLUSION

Less than half of sudden deaths due to CAD had evidence of acute plaque complication, an observation which is contrary to historical perceptions. The prevalence of concomitant myocardial disease was high and independent of associated plaque morphology.

Genetic Variants Associated With Sudden Cardiac Death in Victims With Single Vessel Coronary Artery Disease and Left Ventricular Hypertrophy With or Without Fibrosis

Objective: Cardiac hypertrophy with varying degrees of myocardial fibrosis is commonly associated with coronary artery disease (CAD) related sudden cardiac death (SCD), especially in young victims among whom patterns of coronary artery lesions do not entirely appear to explain the cause of SCD. Our aim was to study the genetic background of hypertrophy, with or without fibrosis, among ischemic SCD victims with single vessel CAD.

Methods: The study population was derived from the Fingesture study, consisting of all autopsy-verified SCDs in Northern Finland between the years 1998 and 2017 (n = 5,869). We carried out targeted next-generation sequencing using a panel of 174 genes associated with myocardial structure and ion channel function in 95 ischemic-SCD victims (mean age 63.6 ± 10.3 years; 88.4% males) with single-vessel CAD in the absence of previously diagnosed CAD and cardiac hypertrophy with or without myocardial fibrosis at autopsy.

Results: A total of 42 rare variants were detected in 43 subjects (45.3% of the study subjects). Five variants in eight subjects (8.4%) were classified as pathogenic or likely pathogenic. We observed 37 variants of uncertain significance in 39 subjects (40.6%). Variants were detected in myocardial structure protein coding genes, associated with arrhythmogenic right ventricular, dilated, hypertrophic and left ventricular non-compaction cardiomyopathies. Also, variants were detected in ryanodine receptor 2 (RYR2), a gene associated with both cardiomyopathies and catecholaminergic polymorphic ventricular tachycardias.

Conclusions: Rare variants associated with cardiomyopathies, in the absence of anatomic evidence of the specific inherited cardiomyopathies, were common findings among CAD-related SCD victims with single vessel disease and myocardial hypertrophy found at autopsies, suggesting that these variants may modulate the risk for fatal arrhythmias and SCD in ischemic disease.

Genetic contributions to the expression of acquired causes of cardiac hypertrophy in non-ischemic sudden cardiac death victims

The contribution of genetic variants to non-ischemic sudden cardiac death (SCD) due to acquired myocardial diseases is unclear. We studied whether SCD victims with hypertension/obesity related hypertrophic myocardial disease harbor potentially disease associated gene variants. The Fingesture study has collected data from 5869 autopsy-verified SCD victims in Northern Finland. Among SCD victims, 740 (13%) had hypertension and/or obesity as the most likely explanation for myocardial disease with hypertrophy and fibrosis. We performed next generation sequencing using a panel of 174 cardiac genes for 151 such victims with the best quality of DNA. We used 48 patients with hypertension and hypertrophic heart as controls. Likely pathogenic variants were identified in 15 SCD victims (10%) and variants of uncertain significance (VUS) were observed in additional 43 SCD victims (28%). In controls, likely pathogenic variants were present in two subjects (4%; p = 0.21) and VUSs in 12 subjects (25%; p = 0.64). Among SCD victims, presence of potentially disease-related variants was associated with lower mean BMI and heart weight. Potentially disease related gene variants are common in non-ischemic SCD but further studies are required to determine specific contribution of rare genetic variants to the extent of acquired myocardial diseases leading to SCD.

Coronary Artery Disease as the Cause of Sudden Cardiac Death Among Victims < 50 Years of Age

Coronary artery disease (CAD) is the most common cause of sudden cardiac death (SCD). Atherosclerosis increases with age, but also many victims of SCD in young and middle-aged population have CAD at autopsy. The purpose of this study was to determine the characteristics and autopsy findings of SCD due to CAD among victims of SCD under the age of 50. Fingesture is a population-based study consisting of consecutive series of victims of autopsy verified SCD in Northern Finland between the years 1998 to 2017 (n = 5,869). Histological examinations were part of all autopsies and a toxicology investigation was performed if needed. Analyses included information accumulated from death certificates, medical records, autopsy data, standardized questionnaire to the closest family members of the victims of SCD and police reports of the conditions of the death. Overall, 10.4% of all SCDs occurred among victims under the age of 50 years (610 victims). Most common underlying cause of SCD among these younger SCD victims was CAD (43.6%). The prevalence of CAD as the cause of SCD became more common in young SCD victims after the age of 35 years. The mean age of ischemic SCD victims was 44±5 years and most were men (89.5%). Most victims (90.2%) had no clinical diagnosis of CAD, however 33.8% had an autopsy evidence of silent myocardial infarction. SCD occurred during physical activity in 24.1%. Three-vessel disease was detected in 44.4% of the study victims. Cardiac hypertrophy (58.3%) and myocardial fibrosis (82.6%) were also common. At least 1 cardiovascular risk factor was present in 64.7% of SCD victims. In conclusion, most SCDs among victims < 50 years of age are due to CAD.

Association of Silent Myocardial Infarction and Sudden Cardiac Death

Importance

Myocardial infarction in the absence of major or unrecognized symptoms are characterized as silent (SMI). The prevalence of SMI among individuals who experience sudden cardiac death (SCD), with or without concomitant electrocardiographic (ECG) changes, has not previously been described in detail from large studies to our knowledge.

Objective

To determine the prevalence of SMI in individuals who experience SCD without a prior diagnosis of coronary artery disease (CAD) and to detect ECG abnormalities associated with SMI-associated SCD.

Design, Setting, and Participants

This case-control study compared autopsy findings, clinical characteristics, and ECG markers associated with SMI in a consecutive cohort of individuals in the Finnish Genetic Study of Arrhythmic Events (Fingesture) study population who were verified to have had SCD. The Fingesture study consists of individuals who had autopsy-verified SCD in Northern Finland between 1998 and 2017. Individuals who had SCD with CAD and evidence of SMI were regarded as having had cases; those who had SCD with CAD without SMI were considered control participants. Analyses of ECG tests were carried out by investigators blinded to the SMI data. Data analysis was completed from October 2018 through November 2018.

Main Outcomes and Measures

Silent MI was defined as a scar detected by macroscopic and microscopic evaluation of myocardium without previously diagnosed CAD. Clinical history was obtained from medical records, previously recorded ECGs, and a standardized questionnaire provided to the next of kin. The hypothesis tested was that SMI would be prevalent in the population who had had SCD with CAD, and it might be detected or suspected from findings on ECGs prior to death in many individuals.

Results

A total of 5869 individuals were included (2459 males [78.8%]; mean [SD] age, 64.9 [12.4] years). The cause of SCD was CAD in 4392 individuals (74.8%), among whom 3122 had no history of previously diagnosed CAD. Two individuals were excluded owing to incomplete autopsy information. An ECG recorded prior to SCD was available in 438 individuals. Silent MI was detected in 1322 individuals (42.4%) who experienced SCD without a clinical history of CAD. The participants with SMI were older than participants without MI scarring (mean [SD] age, 66.9 [11.1] years; 65.5 [11.6] years; P < .001) and were more often men (1102 of 1322 [83.4%] vs 1357 of 1798 [75.5%]; P < .001). Heart weight was higher in participants with SMI (mean [SD] weight, 483 [109] g vs 438 [106] g; P < .001). In participants with SMI, SCD occurred more often during physical activity (241 of 1322 [18.2%] vs 223 of 1798 [12.4%]; P < .001). A prior ECG was abnormal in 125 of the 187 individuals (66.8%) who had SCD after SMI compared with 139 of 251 (55.4%) of those who had SCD without SMI (P = .02).

Conclusions and Relevance

Many individuals who experienced SCD associated with CAD had a previously undetected MI at autopsy. Previous SMI was associated with myocardial hypertrophy and SCD during physical activity. Premortem ECGs in a subset with available data were abnormal in 67% of the individuals who had had a SCD after an SMI.

Prognostic significance of P-wave morphology in patients with coronary artery disease

INTRODUCTION

The prognostic significance of P-wave morphology in patients with coronary artery disease (CAD) is not well-known.

METHODS

A total of 1946 patients with angiographically verified CAD were included in the Innovation to reduce Cardiovascular Complications of Diabetes at the Intersection (ARTEMIS) study. The P-wave morphology could be analyzed in 1797 patients.

RESULTS

During 7.4 ± 2.0 years, a total of 168 (9.3%) patients died or experienced resuscitation from sudden cardiac arrest (SCA), 43 (2.4%) patients experienced sudden cardiac death (SCD) or were resuscitated from SCA, 37 (2.1%) patients succumbed to non-SCD (NSCD), and 88 (4.9%) patients to noncardiac death (NCD). Of the P-wave parameters, the absolute P-wave residuum (PWR), the heterogeneity of the P-wave morphology (PWH), and the P-wave duration (Pdur) had the closest univariate association with the risk of SCD/SCA (0.0038 ± 0.0026 vs 0.0022 ± 0.0017, P < .001; 11.0 ± 5.2 vs 8.6 ± 3.6, P < .01; 142.7 ± 16.9 vs 134.8 ± 14.3 milliseconds, P < .01; SCD/SCA vs no SCD/SCA, respectively). After adjustments with factors that were associated with the risk of SCD/SCA, such as diabetes, smoking, left bundle branch block, high-sensitivity C-reactive protein, and high-sensitivity troponin T, PWR (P < .001), PWH (P < .05), and Pdur (P < 0.01) still predicted SCD/SCA but not non-sudden cardiac death. When these parameters were added to the SCD/SCA clinical risk model, the discrimination and reclassification accuracy of the risk model increased significantly (P < .05, P < .001) and the C-index increased from 0.745 to 0.787.

CONCLUSION

The P-wave morphology parameters independently predict SCD/SCA in patients with CAD.

Temporal Trends in the Clinical and Pathological Characteristics of Victims of Sudden Cardiac Death in the Absence of Previously Identified Heart Disease

Background—

Coronary artery disease is identified in ≈80% of victims of sudden cardiac death (SCD). Because the prevention strategies and public awareness have changed during the past decades, we studied the temporal trends in the pathogenesis of SCD.

Methods and Results—

FinGesture (n=4031) is a prospective study designed to classify the phenotype and genotype profiles of SCD in a consecutive series of victims of SCD in Northern Finland. On the basis of Finnish law, all subjects who die suddenly undergo autopsy. We analyzed the characteristics of SCD victims and autopsy findings in 1998 to 2002, 2003 to 2007, and 2008 to 2012. Among victims of SCD as a first cardiac event (n=2697), the proportion with coronary artery disease decreased during the 2008 to 2012 time period, compared with the 2 preceding 5-year periods: 74.0% in 1998 to 2002, 73.1% in 2003 to 2007, and 66.4% in 2008 to 2012 ( P <0.001). Proportion of SCDs associated with hypertensive heart disease with left ventricular hypertrophy in the absence of coronary artery disease increased from 1.7% in 1998 to 2002 to 5.8% in 2003 to 2007 and 8.9% in 2008 to 2012 ( P <0.001). Similarly, myocardial fibrosis in the absence of myocarditis or left ventricular hypertrophy, or other known pathogeneses, was 6.7% in the past 5-year period compared with 2 previous 5-year periods (3.7% and 4.0%; P <0.001 between 1998–2002 and 2008–2012 and between 2003–2007 and 2008–2012).

Conclusions—

The proportion of SCDs attributable to coronary artery disease, in the absence of a history of heart disease, has decreased, whereas the proportion associated with hypertensive heart disease and idiopathic fibrosis has increased during the past 15 years.

Antiepileptic medications and the risk for sudden cardiac death caused by an acute coronary event: a prospective case-control study

BACKGROUND

Epilepsy is associated with sudden death, but the reasons for this association are not well known. Objective We studied the role of antiepileptic drugs (AEDs) as a factor contributing to sudden cardiac death (SCD) in The Finnish Study of the Genotype and Phenotype Characteristics of Sudden Cardiac Death (FinGesture).

METHODS AND RESULTS

The FinGesture study compares the characteristics of victims of SCD caused by an autopsy-verified acute coronary event (cases) vs. survivors of an acute coronary event (ACS) (controls). The study population comprised 3737 cases (mean age 64 ± 12 y) and 3081 controls (mean age 66 ± 12 y). The use of AED was obtained from death certificates, autopsy/hospital records, national drug imbursement register, and interviews with the relatives. AEDs were more commonly used by the victims of SCD vs. controls (5.5% vs. 2.2%, adjusted odds ratio 2.7, 95% CI; 1.9-3.9; p < 0001). The use of AED for non-epilepsy indications was also more common in the cases than in controls (1.5% vs. 1.0%, p = 0.005).

CONCLUSION

A higher rate of AED was observed in victims of SCD than in a control group of ACS patients. Concomitant use of AED could be responsible for a small fraction of deaths due to acute coronary events. Key message Epilepsy has been associated with sudden cardiac death. The use of antiepileptic drugs seems to be associated with an increased risk of sudden cardiac death during a coronary event. Physicians should be aware of the risk related to antiepileptic drugs especially when used for other reasons than epilepsy.

Heterogeneous associations between smoking and a wide range of initial presentations of cardiovascular disease in 1937360 people in England: lifetime risks and implications for risk prediction

Background It is not known how smoking affects the initial presentation of a wide range of chronic and acute cardiovascular diseases (CVDs), nor the extent to which associations are heterogeneous. We estimated the lifetime cumulative incidence of 12 CVD presentations, and examined associations with smoking and smoking cessation.

Methods Cohort study of 1.93 million people aged ≥30years, with no history of CVD, in 1997–2010. Individuals were drawn from linked electronic health records in England, covering primary care, hospitalizations, myocardial infarction (MI) registry and cause-specific mortality (the CALIBER programme).

Results During 11.6 million person-years of follow-up, 114 859 people had an initial non-fatal or fatal CVD presentation. By age 90 years, current vs never smokers’ lifetime risks varied from 0.4% vs 0.2% for subarachnoid haemorrhage (SAH), to 8.9% vs 2.6% for peripheral arterial disease (PAD). Current smoking showed no association with cardiac arrest or sudden cardiac death [hazard ratio (HR) = 1.04, 95% confidence interval (CI) 0.91–1.19).The strength of association differed markedly according to disease type: stable angina (HR = 1.08, 95% CI 1.01–1.15),transient ischaemic attack (HR = 1.41, 95% CI 1.28-1.55), unstable angina (HR = 1.54, 95% CI 1.38–1.72), intracerebral haemorrhage (HR = 1.61, 95% CI 1.37–1.89), heart failure (HR = 1.62, 95% CI 1.47–1.79), ischaemic stroke (HR = 1.90, 95% CI 1.72–2.10), MI (HR = 2.32, 95% CI 2.20–2.45), SAH (HR = 2.70, 95% CI 2.27–3.21), PAD (HR = 5.16, 95% CI 4.80–5.54) and abdominal aortic aneurysm (AAA) (HR = 5.18, 95% CI 4.61–5.82). Population-attributable fractions were lower for women than men for unheralded coronary death, ischaemic stroke, PAD and AAA. Ten years after quitting smoking, the risks of PAD, AAA (in men) and unheralded coronary death remained increased (HR = 1.36, 1.47 and 2.74, respectively).

Conclusions The heterogeneous associations of smoking with different CVD presentations suggests different underlying mechanisms and have important implications for research, clinical screening and risk prediction.

Association of early repolarization and sudden cardiac death during an acute coronary event

BACKGROUND

Electrocardiographic early repolarization (ER) pattern has been previously associated with arrhythmic mortality and with an increased risk of ventricular fibrillation. We hypothesized that there is an association between ER and sudden cardiac death (SCD) during an acute coronary event.

METHODS AND RESULTS

The present study included 432 consecutive victims of SCD because of acute coronary event and 532 survivors of such an event, in whom 12-lead ECGs recorded before and unrelated to the event could be evaluated. SCDs were verified by medicolegal autopsy to be because of acute coronary event. ER was defined as an elevation of the QRS-ST junction in at least 2 inferior or lateral leads, manifested as QRS notching or slurring. The prevalence of ER pattern ≥0.1 mV was more common in cases (62/432; 14.4%) than controls (42/532; 7.9%) (P=0.001). The victims of SCD were younger, were more commonly men and smokers, had lower body mass index, had elevated heart rate, had prolonged QRS complex, and had lower prevalence of history of prior cardiovascular disease than controls. After adjustments for baseline differences, the odds ratio for J waves without ST-segment elevation in the SCD group was 2.15 (95% CI, 1.20-3.85; P=0.01).

CONCLUSIONS

Higher prevalence of ER in a standard 12-lead ECG in victims of SCD than in survivors of an acute coronary event suggests that the presence of ER increases the vulnerability to fatal arrhythmia during acute myocardial ischemia and provides a plausible mechanistic link between this ECG pattern and higher arrhythmic mortality of middle-aged/elderly subjects.

Sex differences in short- and long-term case-fatality of myocardial infarction

Declining trends in case fatality (CF) of MI events have been generally reported in western countries. It is, however, not clear whether the development has been equally beneficial in both sexes. Data from two large population based registers, FINAMI and the Finnish National Cardiovascular Disease Register (CVDR) were used to determine whether the CF of incident MI events has declined less in women than in men. All patients aged 35 and over were included. CF was calculated for different time periods after the onset of the MI event, the main emphasis was in pre-hospital, 28-day, and 1-year CF. Figures were compared between two study periods: 1994-1996 and 2000-2002. A total of 6,342 incident MI events were recorded in FINAMI and 117,632 events in CVDR during the study periods. Comparison between the two study periods showed that the CF was generally declining. However, a slower decline in short-term CF was seen among young (aged<55 years) women (P for sex by study period interaction in pre-hospital CF=0.028 in FINAMI and 0.003 in CVDR, and for 28-day CF P=0.016 in FINAMI and <0.0001 in CVDR). In conclusion, the short and long-term prognosis of MI events has improved in both sexes. Pre-hospital CF has declined less among younger women than among men and among older women. This slower decline in early CF was responsible for the slower improvement in 28-day and 1-year prognosis in young women.