Presence Of Sudden Death Research Articles

Clinical Implications and Gender Differences of KCNQ1 p.Gly168Arg Pathogenic Variant in Long QT Syndrome.

Background: Long QT syndrome (LQTS) is an inheritable arrhythmogenic disorder associated with life-threatening arrhythmic events (LAEs). In general, patients with LQTS2 (KCNH2) and LQTS3 (SCN5A) are considered to be a greater risk of LAEs than LQTS1 (KCNQ1) patients. Gender differences are also important. Series analyzing families with the same pathogenic variants may help in the progress of elaborating strong specific genotype-phenotype management strategies. In this manuscript, we describe the phenotype of seven unrelated families, carriers of the KCNQ1 G168R pathogenic variant. Methods: we identified all consecutive index cases referred for genetic testing with LQTS diagnosis carriers of KCNQ1 G168R variant. Genetic and clinical screening for all available relatives was performed. Results: we evaluated seven unrelated families, with a total 34 KCNQ1 G168R carriers (two obligated carriers died without available EKGs to evaluate the phenotype). All index cases but one were women and three of them presented with aborted sudden cardiac death (SCD) or syncope. The presence of sudden death in these families is notable, with a total of nine unexplained sudden deaths and four aborted SCD. Phenotype penetrance was 100% in women and 37.5% in men. Conclusions: KCNQ1 G168R is a pathogenic variant, with a high penetrance among women and mild penetrance among men. Risk for LAEs in this variant seems not negligible, especially among woman, and risk stratification should always be carefully evaluated.

Usefulness of Tissue Doppler Imaging to Identify Low Risk Patients with Diagnosis of Hypertrophic Cardiomyopathy

Usefulness of Tissue Doppler Imaging to Identify Low Risk Patients with Diagnosis of Hypertrophic Cardiomyopathy Background Pulsed tissue Doppler imaging is a useful tool for the early detection of hypertrophic cardiomyopathy and the differential diagnosis of this disease from other secondary causes of hypertrophy. Objective The aim of the study was to determine the prognostic significance of preserved systolic tissue velocities in patients with diagnosis of hypertrophic cardiomyopathy. Methods One hundred and forty six patients with diagnosis of hypertrophic cardiomyopathy were prospectively included by means of a Doppler echocardiography study. Systolic tissue velocities were obtained from the averaged septal and lateral velocities. Patients with preserved systolic tissue velocities (Sa ≥ 8 cm/s; upper quartile) were compared with those presenting decreased velocities. The primary endpoint was defined as the presence of sudden death, stroke, heart failure, or hospitalization for cardiovascular causes at follow up. Results Twenty nine percent of patients (n = 43) presented preserved systolic tissue velocities in the tissue Doppler images, mostly in men (76.7% vs. 53.4%, p = 0.009) and with no age differences. Ventricular diameter and thickness were similar between the two groups while the atrial area was significantly lower (23.7 ± 6.7 vs. 28.8 ± 8, p <0.01). At follow up (median of 2.7 years), the number of events increased significantly as systolic pulsed tissue Doppler velocities decreased. No patient from the group with preserved systolic tissue velocities presented the combined endpoint, with significant differences with respect to the control group (0% vs. 21.6%, p = 0.001), and a negative predictive value of 100%. Conclusions In our population with hypertrophic cardiomyopathy, the presence of preserved systolic tissue velocities in pulsed tissue Doppler imaging identified low-risk patients with a very low number of events at follow up and high negative predictive value.

Study of a Colombian Family with Hypertrophic Cardiomyopathy and Sudden Cardiac Death Associated with the Lys247arg Mutation in the Cardiac Troponin T (Tnnt2) Gene: Casual Relationship or Polymorphism?

Introduction and Objectives: Hypertrophic cardiomyopathy is the most common genetic cardiovascular disease. Mutations have been described in at least 27 genes that can encode sarcomere proteins, mitochondrial proteins and proteins that control calcium handling. This report shows a family with Hypertrophic cardiomyopathy in the presence of sudden death. Methods: We performed a clinical, genetic and molecular biology to establish the phenotypic and genotypic commitment of this disease. We analyzed a total of 592 mutations in 16 genes spread ACTC, GLA, MYBPC3, MYH6, MYH7, MYL2, MYL3, MYLK2, MYO6, PRKAG2, TCAP, TNN1, TNNI3, TNN2, TPM1 and TTN. Results: We determined phenotypic and genotypic characteristics of 37 members belonging to one family in five generations. Lys247Arg (K247R) mutation was found in 13 family members (38.23%) of which 3 had hypertrophy on echocardiography, but two patients had hypertrophy and they did not have the mutation. Moreover, a patient carries the mutation but the mother does not. The father (not related to the family) carries this mutation. Conclusions: We present a Colombian family with hypertrophic cardiomyopathy and sudden death where described causal mutations in the sarcomeric genes were evaluated. K247R genetic variant in the Troponin T type 2 gene was found with no correspondence to the phenotypic expresion of the disease in the family.

Analysis of the outcomes of cardiopulmonary resuscitation in an emergency department

Objective — The aim of this study is to analyse the factors affecting emergency department (ED) cardiopulmonary resuscitation (CPR) outcome.Methods — A standard CPR protocol was performed in all patients and certain pre and postresuscitation parameters including age, sex, initial arrest rhythm, primary underlying disease, initiation time of advanced cardiac life support, duration of return of spontaneous circulation were recorded. Patients were followed up to determine rates of successful CPR, survival and one-year survival.Results — From December 1999 to May 2001, 80 consecutive adult patients in whom a standard CPR was performed in the ED were prospectively included in the study.The overall rate for successful CPR, survival and one-year survival were found to be 58.8% (47/80), 15% (12/80) and 10% (8/80), respectively. Survival and one-year survival rates were better in patients with an initial arrest rhythm of ventricular fibrillation or pulseless ventricular tachycardia (VF/pVT) than both pulseless electrical activity (pEA) and asystole; survival and one-year survival rates were better in patients with a primary underlying disease of cardiac origin than non-cardiac origin. Acute myocardial infarction had the best prognosis among conditions causing arrest. Presence of sudden death was found to have a better survival and one-year survival rate.Conclusion — Initial cardiac rhythm of VF/pVT, cardiac origin as the primary disease causing cardiopulmonary arrest and presence of sudden death were found to be good prognostic factors in CPR.