We hypothesized that myocardial septal scarring, assessed by cardiac magnetic resonance (CMR) using late gadolinium enhancement (LGE), at the site of cardiac contractility modulation (CCM) lead ...placement may predict treatment response. Eligible heart failure (HF) patients underwent LGE CMR imaging before CCM device implantation. The response to CCM therapy at follow-up was determined by a change in NYHA class and echocardiographic left ventricular ejection fraction (LVEF) assessment. Patients were classified as responders, if they showed an improvement in either NYHA class or improvement of LVEF by ≥ 5%. 58 patients were included. 67% of patients were classified as responders according to improved NYHA; 55% according to LVEF improvement. 74% of patients were responders if either NYHA class or LVEF improvement was observed. 90% of responders (according to NYHA class) showed septal LGE < 25% at septal position of the leads, while 44% of non-responders showed septal LGE > 25% (p < 0.01). In patients treated with CCM, an improvement of NYHA class was observed when leads were placed at myocardial segments with a CMR- LGE burden less than 25%.
The subcutaneous implantable cardioverter-defibrillator (S-ICD) is an implantable device for antiarrhythmic therapy with no intravascular leads.
The purpose of this study was to describe the ...technical feasibility of combining the S-ICD with other cardiac implantable electronic devices (CIEDs), including pacemakers with transvenous or epicardial electrodes. We also provide the first experience of combining an S-ICD with catheter-based therapies, including cardiac contractility modulation (CCM) and vagus nerve stimulation.
Between July 2011 and November 2014, 6 patients received a CCM device and S-ICD, 3 patients with a single-chamber pacemaker using either transvenous or epicardial pacing electrodes received and S-ICD, and 1 patient with an implanted S-ICD received vagus nerve stimulation. In all patients, intraoperative S-ICD testing, crosstalk tests, and postoperative ergometric testing were performed.
In all 10 patients, device implantations were successfully performed without complications. S-ICD therapy was shown to be technically feasible with concomitant CIED. Mean follow-up was nearly 17 months. S-ICD testing and crosstalk testing before and during exercise enabled device programming across a broad range of test conditions and was associated with no subsequent evidence of adverse device interaction. None of the devices required permanent inactivation or removal, and no patient received an inappropriate shock.
In suitable patients, combining an S-ICD with CCM or pacemaker may provide an acceptable means to reduce the number of transvascular leads. S-ICD appeared safe with CCM over an intermediate follow-up period. Additional prospective randomized controlled trials examining S-ICD in conjunction with CIEDs are warranted.
Fever can increase the susceptibility to supraventricular and ventricular arrhythmias, in which sodium channel dysfunction has been implicated. Whether fever influences the efficacy of sodium channel ...blocking drugs is unknown. The current study was designed to investigate the temperature dependent effects of distinct sodium channel blocking drugs on the sodium currents in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).
hiPSC-CMs were generated from human skin fibroblasts of a healthy donor. The peak and late sodium currents (INa), steady-state activation, inactivation and recovery from inactivation of INa in hiPSC-CMs were analyzed using the whole-cell patch clamp technique. The effects of different concentrations of the antiarrhythmic drugs flecainide, lidocaine, ajmaline and the antianginal drug ranolazine on INa were tested at 36°C and 40°C. Increasing the temperature of the bath solution from 36°C to 40°C enhanced the inhibition of peak INa but reduced the inhibition of late INa by flecainide and lidocaine. By contrast, increasing the temperature reduced the effect of ajmaline and ranolazine on the peak INa but not late INa. None of the tested drugs showed temperature-dependent effects on the steady-state activation and inactivation as well as on the recovery from inactivation of INa in hiPSC-CMs.
Temperature variation from the physiological to the febrile range apparently influences the effects of sodium channel blockers on the sodium currents. This may influence their antiarrhythmic efficacy in patients suffering from fever.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Short QT syndrome (SQTS) is associated with sudden cardiac arrest. There are limited data on the impact of antiarrhythmic drugs on the outcome of SQTS.
We studied data that describe the clinical ...outcome of 62 SQTS patients treated with antiarrhythmic drugs, who were recruited from a pool of patients diagnosed in our institution and also from known databases after a systematic search of the published literature.
Sixty-two SQTS patients treated with antiarrhythmic drugs were followed up over a median timeframe of 5.6 years (interquartile range 1.6-7.7 years). Six patients, in particular, received multiple drugs as a combination. Of the 55 patients treated with hydroquinidine (HQ), long-term prophylaxis was documented in 41 patients. Fourteen patients stopped treatment due to the following reasons: gastrointestinal intolerance (n = 4), poor compliance (n = 8), and no QTc prolongation (n = 2). Of the 41 patients treated with HQ, the QTc interval increased from 313.5 ± 17.2 to 380.1 ± 21.2 ms. Thirteen of the 41 patients suffered from at least one or more ventricular tachyarrhythmias (VAs) before HQ initiation. VAs are reduced in incidence after HQ treatment (13/41: 31% versus 3/41: 7.3%, p < 0.001).
HQ increases the corrected QT interval and prevents VAs in the majority of the patients in this cohort. HQ is safe for use in SQTS patients, particularly due to its low rate of side effects. Other antiarrhythmic drugs might be useful, but the data justifying their use are sparse.
Background Short QT syndrome ( SQTS ) is a rare inheritable disease associated with sudden cardiac death. Data on long-term outcomes of families with SQTS are limited. Methods and Results Seventeen ...patients with SQTS in 7 independent families (48% men; median age, 42.4 years; corrected QT interval, 324.9±40.8 ms) were followed up for 13.5±2.5 years. A history of sudden cardiac death was documented in 71% of families. A large number of them showed sudden cardiac deaths at a younger age, with a predominance of men (67%). Five patients had syncope (29%) and 9 (53%) had atrial fibrillation or atrial flutter. An SQTS -related gene was found in 76% of the patients as follows: KCNH 2 ( SQTS 1) in 4, CACNA 1C ( SQTS 4) in 3, and CACN b2 ( SQTS 5) in 6. Five patients (29%) received an implantable cardioverter-defibrillator and 5 patients received long-term prophylaxis with hydroquinidine. During follow-up, 1 patient received an appropriate implantable cardioverter-defibrillator shock attributable to ventricular fibrillation. The patient received no further implantable cardioverter-defibrillator shocks after treatment with hydroquinidine. Conclusions The risk of sudden cardiac death in SQTS families is high. However, after appropriate risk assessment and individualized treatment options (hydroquinidine and/or implantable cardioverter-defibrillator), the long-term outcome is relatively benign when patients are seen at a reference center.
Background: Sacubitril/valsartan decreased the risk of sudden cardiac death (SCD) in patients suffering from heart failure with reduced ejection fraction (HFrEF). However, long-term data are sparse. ...Objective: The aim of the present study was to compare the incidence of life-threatening arrhythmias consisting of ventricular tachycardia and/or ventricular fibrillation before and after initiation of sacubitril/valsartan treatment. Methods: Out of 12,000 patients with HFrEF from 2016–2018, 148 patients were newly prescribed sacubitril/valsartan, but the long-term data of only 127 patients were available and included in this study. Results: Patients with an average age of 66.8 ± 12.1 had a median left ventricular ejection fraction (LVEF) of 25% (interquartile range (IQR) 5.00–45.00) and 30% (IQR 10.00–55.00, p < 0.0005) before and after sacubitril/valsartan treatment, respectively. Systolic blood pressure decreased from 127.93 ± 22.01 to 118.36 ± 20.55 mmHg (p = 0.0035) at 6 months of follow-up. However, in 59 patients with a long-term outcome of 12 months, ventricular arrhythmias persistently increased (ventricular fibrillation from 27.6 to 29.3%, ventricular tachycardia (VT) from 12% to 13.8%, and nonsustained VT from 26.6 to 33.3%). Conclusions: Sacubitril/valsartan does not reduce the risk of ventricular tachyarrhythmias in chronic HFrEF patients over 12 months of follow-up.
Short QT syndrome (SQTS) is a rare syndrome and affects different types of genes. However, data on differences of clinical profile and outcome of different SQTS types are sparse.
We conducted a ...pooled analysis of 110 SQTS patients. Patients have been diagnosed between 2000 and 2017 at our institution (n = 12) and revealed using a literature review (n = 98). 29 studies were identified by analysing systematic data bases (PubMed, Web of Science, Cochrane Libary, Cinahl).
67 patients with genotype positive SQTS origin and 43 patients with genotype negative origin were found. A significant difference is documented between the sex with a higher predominance of male in genotype negative SQTS patients and predominance of females in genotype positive SQTS patients (male 52% versus 84%, female 45% versus 14%; p = 0.0016). No relevant difference of their median age (genotype positive 27 ± 19 versus genotype negative 29 ± 15; p = 0.48) was found. Asymptomatic patients and patients reporting symptoms such as syncope, sudden cardiac death, atrial flutter and ventricular fibrillation documented in both groups were similar except atrial fibrillation (genotype positive 19% versus genotype negative 0%; p = 0.0055). The QTc interval was not significantly different in both groups (genotype positive 315 ± 32 versus genotype negative 320 ± 19; p = 0.30). The treatments (medical treatment and ICD implantation) in both groups were comparable. Electrophysiology studies were not significantly higher documented in patients with genotype positive and negative origin (24% versus 9%; p = 0.075). Events at follow up such as VT, VF, and SCD were not higher presented in patients with genotype positive (13% versus 9%) (p = 0.25). 54% of genotype positive SQTS patients showed SQTS 1 followed by STQS 2 (21%) and SQTS 3 (10%).
The long-term risk of a malignant arrhythmic event is not higher in patients with genotype positive. However, patients with genotype positive present themselves more often with AF with a female predominance. Also, other events at follow up such as syncope, atrial flutter and palpitation were not significantly higher (9% versus 0%; p = 0.079).
Background
Up to 40% of patients with transvenous implantable cardioverter‐defibrillator (ICD) experience lead‐associated complications and may suffer from high complication rates when lead ...extraction is indicated. Subcutaneous ICD may represent a feasible alternative; however, the efficacy of the subcutaneous ICD in the detection and treatment of ventricular arrhythmias in patients with hereditary arrhythmia syndromes has not been fully evaluated.
Methods and Results
Patients with primary hereditary arrhythmia syndromes who fulfilled indication for defibrillator placement were eligible for enrollment. Between 2010 and 2016, 62 consecutive patients with primary hereditary arrhythmia syndromes, without indication for antibradycardia therapy, were enrolled in the study. Mean follow‐up was 31.0±14.2 months. The study cohort comprised of 24 patients with Brugada syndrome, 17 with idiopathic ventricular fibrillation, 6 with long‐QT syndrome, 1 with short‐QT syndrome, 3 with catecholaminergic polymorphic ventricular tachycardia, 8 with hypertrophic cardiomyopathy, and 3 with arrhythmogenic right ventricular cardiomyopathy. Thirty‐nine patients were implanted for secondary prevention. Twenty‐two patients had a previous transvenous ICD implanted, but required revision because of infection or lead defects. A total of 20 spontaneous ventricular tachyarrhythmias requiring shock intervention occurred in 10 patients during follow‐up. All episodes were terminated within the first ICD shock delivery with 80 J. Two patients had inappropriate therapies caused by oversensing following an uneventful implantation. No pocket‐site infections and no premature revisions have occurred during follow‐up.
Conclusions
Our study supports the use of the subcutaneous ICD for both secondary and primary prevention of sudden cardiac death as a reliable alternative to the conventional transvenous ICD.
Background
The underlying mechanisms of Brugada syndrome (BrS) are not completely understood. Recent studies provided evidence that the electrophysiological substrate, leading to electrocardiogram ...abnormalities and/or ventricular arrhythmias, is located in the right ventricular outflow tract (RVOT). The purpose of this study was to examine abnormalities of epicardial and endocardial local unipolar electrograms by simultaneous noninvasive mapping in patients with BrS.
Methods and Results
Local epicardial and endocardial unipolar electrograms were analyzed using a novel noninvasive epi‐ and endocardial electrophysiology system (NEEES) in 12 patients with BrS and 6 with right bundle branch block for comparison. Fifteen normal subjects composed the control group. Observed depolarization abnormalities included fragmented electrograms in the anatomical area of RVOT endocardially and epicardially, significantly prolonged activation time in the RVOT endocardium (65±20 vs 38±13 ms in controls; P=0.008), prolongation of the activation‐recovery interval in the RVOT epicardium (281±34 vs 247±26 ms in controls; P=0.002). Repolarization abnormalities included a larger area of ST‐segment elevation >2 mV and T‐wave inversions. Negative voltage gradient (−2.5 to −6.0 mV) between epicardium and endocardium of the RVOT was observed in 8 of 12 BrS patients, not present in patients with right bundle branch block or in controls.
Conclusions
Abnormalities of epicardial and endocardial electrograms associated with depolarization and repolarization properties were found using NEEES exclusively in the RVOT of BrS patients. These findings support both, depolarization and repolarization abnormalities, being operative at the same time in patients with BrS.
Background/Aim: Despite advances in the treatment strategies of patients with atrial fibrillation (AF), the risk of AF recurrences is still over 50%. An increased left atrial volume index (LAVI) ...reflects left ventricular diastolic dysfunction (DD) and
deterioration of the LA function.
This study aims to determine AF recurrence following cardioversion (CV) or catheter ablation for AF (pulmonary vein isolation; PVI) in dependence of DD and LAVI. Patients and Methods: One hundred and sixty-two patients with paroxysmal or persistent AF
in whom either
CV or PVI
were performed
were
included and
followed over a mean of 22.9±3.8 months. Recurrence was defined as any recurrence of AF that occurred 3 months following the procedure.
DD and LAVI were assessed using transthoracic echocardiography (TTE). Results: Recurrent AF occurred in 100 (61.7%) patients, predominantly following CV CV 41 (76.2%) vs. PVI 59 (54.6%), p<0.0001. Both DD and an increased LAVI were more common in the recurrence-group DD 46.0% vs.
14.5%,
p=0.0001; LAVI (ml/m
2
)
49.0±18.6 vs. 26.3±
7.0, p<0.0001. ROC analysis revealed LAVI>36 ml/m
2
as cut-off (p<0.0001, AUC=0.92, 95%CI=0.87-0.97, sensitivity=76%, specificity=94%). In the m
ultivariate
analysis,
DD (HR=1.6, 95%CI=1.3-2.1, p=0.04) and LA enlargement (defined as LAVI>36 ml/m
2
with HR=2.1, 95%CI=1.8-2.7, p<0.0001) could be identified as independent predictors of AF recurrence after attempting to control the heart rhythm. Conclusion: LA enlargement and DD are independent risk factors associated with AF recurrence after initial successful rhythm control attempt.
These findings have implications for timing of either ablation or CV.
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