Diagnostic electrocardiographic trap: A case of conduction system pacing.

His-bundle pacing (HBP) is a relatively new method of cardiac pacing, with recent studies showing an association between HBP and a lower risk of developing right ventricular heart failure compared to classical pacing methods. However, HBP is also associated with a higher risk of lead dislodgement, undersensing, and loss of capture. As such, a detailed assessment of pacing effectiveness in pacemaker patients is vital. In the presented case, an electrocardiogram (ECG) recording seems to present successful selective His-bundle pacing, while pacemaker follow-up demonstrated the loss of ventricular capture. In conclusion, patients receiving HBP should undergo ECG alongside pacing parameter analysis and pacing electrograms, as differences in successful and unsuccessful pacing ECG can be very subtle.

Association of left atrial enlargement and increased left ventricular wall thickness with arrhythmia recurrence after cryoballoon ablation for atrial fibrillation.

BACKGROUND: Left atrial enlargement (LAE) predicts atrial fibrillation (AF) recurrence after cryoballoon-based pulmonary vein isolation (CB). Increased left ventricular wall thickness (LVWT) is pathophysiologically associated with LAE and atrial arrhythmias. AIMS: To assess effect of increased LVWT on long-term outcomes of CB depending on coexistence of LAE. METHODS: LAE was defined using either echocardiography ( > 48 cm³/m²) or multislice computer tomography (MSCT, ≥63 cm³/m²). Increased LVWT was echocardiographic septal/posterior wall thickness > 10 mm in males and > 9 mm in females. All patients achieved 2-year follow-up. RESULTS: Of 250 patients (median [interquartile range, IQR] age of 61 [49.0-67.3] years; 30% female) with AF (40% non-paroxysmal), 66.5% had hypertension, and 27.2% underwent redo procedure. MSCT was done in 76%. During follow-up of 24.5 (IQR, 6.0-31.00) months the clinical success rate was 72%, despite 46% of patients having arrhythmia recurrence. Arrhythmia recurrence risk was increased by LAE and increased LVWT (hazard ratio [HR], 1.801; P = 0.002 and HR, 1.495; P = 0.036; respectively). The highest arrhythmia recurrence (61.9% at 2 years) was among patients with LAE and increased LVWT (33.6% of patients); intermediate (41.8%) among patients with isolated LAE; and lowest among patients with isolated increased LVWT or patients without LAE or increased LVWT (36.8% and 35.2% respectively, P = 0.004). After adjustment for body mass index (BMI), paroxysmal AF, CHA2DS2-VASc score, clinically-significant valvular heart disease, and cardiomyopathy, patients with LAE and concomitant increased LVWT diagnosis had a 1.8-times increased risk of arrhythmia recurrence (HR, 1.784; 95% confidence interval [CI], 1.017-3.130; P = 0.043). CONCLUSION: Joint occurrence of LAE and increased LVWT is associated with the highest rate of arrhythmia recurrence after CB for AF.

Acute Hemodynamic Effects of Simultaneous and Sequential Multi-Point Pacing in Heart Failure Patients With an Expected Higher Rate of Sub-response to Cardiac Resynchronization Therapy: Results of Multicenter SYNSEQ Study.

The aim of the SYNSEQ (Left Ventricular Synchronous vs. Sequential MultiSpot Pacing for CRT) study was to evaluate the acute hemodynamic response (AHR) of simultaneous (3P-MPP syn) or sequential (3P-MPP seq) multi-3-point-left-ventricular (LV) pacing vs. single point pacing (SPP) in a group of patients at risk of a suboptimal response to cardiac resynchronization therapy (CRT). Twenty five patients with myocardial scar or QRS ≤ 150 or the absence of LBBB (age: 66 ± 12 years, QRS: 159 ± 12 ms, NYHA class II/III, LVEF ≤ 35%) underwent acute hemodynamic assessment by LV + dP/dtmax with a variety of LV pacing configurations at an optimized AV delay. The change in LV + dP/dt max (%ΔLV + dP/dt max) with 3P-MPP syn (15.6%, 95% CI: 8.8%-22.5%) was neither statistically significantly different to 3P-MPP seq (11.8%, 95% CI: 7.6-16.0%) nor to SPP basal (11.5%, 95% CI:7.1-15.9%) or SPP mid (12.2%, 95% CI:7.9-16.5%), but higher than SPP apical (10.6%, 95% CI:5.3-15.9%, p = 0.03). AHR (defined as a %ΔLV + dP/dt max ≥ 10%) varied between pacing configurations: 36% (9/25) for SPP apical, 44% (11/25) for SPP basal, 54% (13/24) for SPP mid, 56% (14/25) for 3P-MPP syn and 48% (11/23) for 3P-MPP seq.Fifteen patients (15/25, 60%) had an AHR in at least one pacing configuration. AHR was observed in 10/13 (77%) patients with a LBBB but only in 5/12 (42%) patients with a non-LBBB (p = 0.11). To conclude, simultaneous or sequential multipoint pacing compared to single point pacing did not improve the acute hemodynamic effect in a suboptimal CRT response population. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT02914457.

Prevalence and management of driveline infections in mechanical circulatory support - a single center analysis.

BACKGROUND: Driveline infections in continuous-flow left ventricular assist devices (cf-LVAD) remain the most common adverse event. This single-center retrospective study investigated the risk factors, prevalence and management of driveline infections. METHODS: Patients treated after cf-LVAD implantation from December 2014 to January 2020 were enrolled. Baseline data were collected and potential risk factors were elaborated. The multi-modal treatment was based on antibiotic therapy, daily wound care, surgical driveline reposition, and heart transplantation. Time of infection development, freedom of reinfection, freedom of heart transplantation, and death in the follow-up time were investigated. RESULTS: Of 75 observed patients, 26 (34.7%) developed a driveline infection. The mean time from implantation to infection diagnosis was 463 (±399; range, 35-1400) days. The most common pathogen was Staphylococcus aureus (n = 15, 60%). First-line therapy was based on antibiotics, with a primary success rate of 27%. The majority of patients (n = 19; 73.1%) were treated with surgical reposition after initial antibiotic therapy. During the follow-up time of 569 (±506; range 32-2093) days, the reinfection freedom after surgical transposition was 57.9%. Heart transplantation was performed in eight patients due to resistant infection. The overall mortality for driveline infection was 11.5%. CONCLUSIONS: Driveline infections are frequent in patients with implanted cf-LVAD, and treatment does not efficiently avoid reinfection, leading to moderate mortality rates. Only about a quarter of the infected patients were cured with antibiotics alone. Surgical driveline reposition is a reasonable treatment option and does not preclude subsequent heart transplantation due to limited reinfection freedom.

Utilization of Subcutaneous Cardioverter-Defibrillator in Poland and Europe-Comparison of the Results of Multi-Center Registries.

The implantation of a subcutaneous cardioverter-defibrillator (S-ICD) may be used instead of a traditional transvenous system to prevent sudden cardiac death. Our aim was to compare the characteristics of S-ICD patients from the multi-center registry of S-ICD implantations in Poland with the published results of the European Snapshot Survey on S-ICD Implantation (ESSS-SICDI). We compared data of 137 Polish S-ICD patients with 68 patients from the ESSS-SICDI registry. The groups did not differ significantly in terms of sex, prevalence of ischemic cardiomyopathy, concomitant diseases, and the rate of primary prevention indication. Polish patients had more advanced heart failure (New York Heart Association (NYHA) class III: 11.7% vs. 2.9%, NYHA II: 48.9% vs. 29.4%, NYHA I: 39.4% vs. 67.7%, p < 0.05 each). Young age (75.9% vs. 50%, p < 0.05) and no vascular access (7.3% vs. 0%, p < 0.05) were more often indications for S-ICD. The percentage of patients after transvenous system removal due to infections was significantly higher in the Polish group (11% vs. 1.5%, p < 0.05). In the European population, S-ICD was more frequently chosen because of patients' active lifestyle and patients' preference (both 10.3% vs. 0%, p < 0.05). Our analysis shows that in Poland, compared to other European countries, subcutaneous cardioverters-defibrillators are being implanted in patients at a more advanced stage of chronic heart failure. The most frequent reason for choosing a subcutaneous system instead of a transvenous ICD is the young age of a patient.

A novel risk model for predicting potentially life-threatening arrhythmias in non-ischemic dilated cardiomyopathy (DCM-SVA risk).

BACKGROUND: Non-ischemic dilated cardiomyopathy (DCM) can be complicated by sustained ventricular arrhythmias (SVA) and sudden cardiac death (SCD). By now, left-ventricular ejection fraction (LV-EF) is the main guideline criterion for primary prophylactic ICD implantation, potentially leading either to overtreatment or failed detection of patients at risk without severely impaired LV-EF. The aim of the European multi-center study DETECTIN-HF was to establish a clinical risk calculator for individualized risk stratification of DCM patients. METHODS: 1393 patients (68% male, mean age 50.7 ± 14.3y) from four European countries were included. The outcome was occurrence of first potentially life-threatening ventricular arrhythmia. The model was developed using Cox proportional hazards, and internally validated using cross validation. The model included seven independent and easily accessible clinical parameters sex, history of non-sustained ventricular tachycardia, history of syncope, family history of cardiomyopathy, QRS duration, LV-EF, and history of atrial fibrillation. The model was also expanded to account for presence of LGE as the eight8h parameter for cases with available cMRI and scar information. RESULTS: During a mean follow-up period of 57.0 months, 193 (13.8%) patients experienced an arrhythmic event. The calibration slope of the developed model was 00.97 (95% CI 0.90-1.03) and the C-index was 0.72 (95% CI 0.71-0.73). Compared to current guidelines, the model was able to protect the same number of patients (5-year risk ≥8.5%) with 15% fewer ICD implantations. CONCLUSIONS: This DCM-SVA risk model could improve decision making in primary prevention of SCD in non-ischemic DCM using easily accessible clinical information and will likely reduce overtreatment.

Pregnancy-related cardiac non-elective hospitalizations and pregnancy outcomes. A tertiary referral cardiac center experience.

BACKGROUND: Pregnant women with cardiovascular diseases (CVD) and their offspring are at higher risk of morbidity and mortality. AIMS: To provide data on pregnancy outcomes among women with different types of CVD requiring non-elective cardiac hospitalization in a tertiary referral cardiac center. METHODS: We identified all records of non-elective hospitalizations of pregnant women hospitalized between January 2009 through March 2018, at our institution - a tertiary referral cardiac center. The incidence and types of cardiac complications during pregnancy, as well as the pregnancy and offspring outcomes, were determined. RESULTS: One hundred and sixty-one out of 328 pregnancy-related hospitalizations in 140 pregnancies were non-elective. Cardiac complications occurred in 62 (44%) pregnancies, with the most frequent being episodes of arrhythmia (22.1% pregnancies), followed by heart failure exacerbations (6.4% pregnancies). Maternal mortality reached 2.1% and affected only women with primary cardiomyopathies (CMP). Offspring mortality was 2.8%. Newborns of mothers with cardiac complications had significantly lower Apgar scores and gestational age at delivery, compared to mothers without cardiac complications. CONCLUSIONS: In our series mortality and morbidity among pregnant women with CVD hospitalizations were high. An unfavorable maternal outcome mainly affected women with CMP. Offspring of mothers with cardiovascular complications are prone to have a lower gestational age and Apgar score.

A Novel DSP Truncating Variant in a Family with Episodic Myocardial Injury in the Course of Arrhythmogenic Cardiomyopathy-A Possible Role of a Low Penetrance NLRP3 Variant.

Mono-allelic dominant mutations in the desmoplakin gene (DSP) have been linked to known cardiac disorders, such as arrhythmogenic right ventricular cardiomyopathy and dilated cardiomyopathy. During the course of DSP cardiomyopathy, episodes of acute myocardial injury may occur. While their mechanisms remain unclear, myocarditis has been postulated as an underlying cause. We report on an adolescent girl with arrhythmogenic biventricular cardiomyopathy and three acute myocarditis-like episodes in whom we found a novel truncating DSP variant accompanied by a known low penetrance R490K variant in the NLRP3. Upon family screening, other carriers of the DSP variant have been identified in whom only mild cardiac abnormalities were found. We hypothesized that the uncommon course of cardiomyopathy in the proband as well as striking discrepancies in the phenotype observed in her family may be explained by the co-existence of her low penetrance genetic autoinflammatory predisposition.

A combination of quinidine/mexiletine reduces arrhythmia in dilated cardiomyopathy in two patients with R814W SCN5A mutation.

SCN5A gene mutations are described in 2% of patients with dilated cardiomyopathy (DCM) and different rhythm disturbances, including multifocal ectopic Purkinje-related premature contractions. Recent data indicate that sodium channel blockers are particularly effective monotherapy in carriers of the R222Q SCN5A variant. Our purpose is to describe the effectiveness of antiarrhythmic treatment in a family with genetically determined arrhythmogenic DCM associated with the R814W variant in the SCN5A gene. We examined a family with arrhythmogenic DCM (multifocal ectopic Purkinje-related premature contractions phenotype, atrial tachyarrhythmias, automatism, and conduction disorders) and described antiarrhythmic treatment efficacy in heart failure symptoms reduction and myocardial function improvement. We found a heterozygotic mutation R814W in SCN5A by whole exome sequencing in the proband and confirmed its presence in all affected subjects. There were two sudden cardiac deaths and one heart transplantation among first-degree relatives. The 58-year-old father and his 37-year-old daughter had full spectrum of symptoms associated with R814W SCN5A mutation. Both had implanted cardioverter defibrillator. In the father, adding mexiletine to quinidine therapy reduced ventricular arrhythmia (50-60% â†’ 6-8% of whole rhythm) and reverted long-standing atrial fibrillation to sinus rhythm. In the daughter, mexiletine and overdrive pacing were effective in ventricular arrhythmia reduction (25% â†’ 0.01%). Because of a growing number of atrial fibrillation recurrences, a reduced dose of quinidine (subsequently flecainide) was added, resulting in arrhythmia significant reduction. In both cases, antiarrhythmic effectiveness correlated with clinical improvement. In SCN5A R814W-associated DCM, a combination of Class I antiarrhythmics and overdrive pacing is an effective treatment of severe ventricular and atrial arrhythmias.

Rapid and effective response of the R222Q SCN5A to quinidine treatment in a patient with Purkinje-related ventricular arrhythmia and familial dilated cardiomyopathy: a case report.

BACKGROUND: Mutations of the SCN5A gene are reported in 2-4% of patients with dilated cardiomyopathy (DCM). In such cases, DCM is associated with different rhythm disturbances such as the multifocal ectopic Purkinje-related premature contractions and atrial fibrillation. Arrhythmia often occurs at a young age and is the first symptom of heart disease. CASE PRESENTATION: We present the case of 55-year old male with a 30-year history of heart failure (HF) in the course of familial DCM and complex ventricular tachyarrhythmias, which constituted 50-80% of the whole rhythm. The patient was qualified for heart transplantation because of the increasing symptoms of HF. We revealed the heterozygotic R222Q mutation in SCN5A by means of whole exome sequencing. After the quinidine treatment, a rapid and significant reduction of ventricular tachyarrhythmias and an improvement in the myocardial function were observed and this effect remained constant in the 2.5-year follow-up. This effect was observed even in the presence of concomitant coronary artery disease. CONCLUSIONS: Patients with familial DCM and Purkinje-related ventricular arrhythmias should be offered genetic screening. The quinidine treatment for the SCN5A R222Q mutation can be life saving for patients.

Characteristic features of patients with multiple accessory pathways.

Objective Only limited clinical and electrophysiological data concerning patients (pts) with multiple accessory pathways (MAP) in comparison to large control groups are available. The aim of our study was to analyse these data from the largest cohort of patients with multiple accessory pathways and a large control group. Method and results We analysed data from pts with MAP (group 1) and pts with a single accessory pathway (AP) (group 2) referred for radiofrequency catheter ablation (RFCA) at our tertiary centre. Group 1 consisted of 124 pts (M 62.10%, mean age 33.00 ± 5.26) with MAP and RFCA. Group 2 consisted of 376 pts (M 51.20%, mean age 35.87 ± 16.15) with a single accessory pathway and RF ablation. Group 1 exhibited a higher incidence of overt APs (P < 0.0001), Ebstein anomaly (P = 0.001), ventricular fibrillation (P = 0.012), antidromic atrioventricular re-entrant tachycardia (A AVRT) (P = 0.025) and male gender (P = 0.038). The mean age at the first documented atrioventricular re-entrant tachycardia (AVRT) episode was lower in pts with MAP than in pts with single APs: 16.79 ± 13.41 vs 20.84 ± 14.29, respectively (P = 0.001). Concealed accessory pathways (P < 0.0001) occurred more frequently in the control group. Group 1 had more right-lateral (P = 0.0001), mid-septal (P = 0.0001), left-posterior (P = 0.01), left-anterior (P = 0.013) and left-lateral localizations of AP (P < 0.037). Conclusions The MAP group included statistically significantly more men, Ebstein anomaly and overt APs. The mean age of the first episode of atrioventricular re-entrant tachycardia was lower in pts with MAP. Certain distribution patterns are apparent for single and MAP. Pts with MAP are at higher risk of VF and antidromic atrioventricular re-entrant tachycardia.

Risk factors of atrial fibrillation recurrence despite successful radiofrequency ablation of accessory pathway: At 11 years of follow-up.

BACKGROUND: Previous reports on patients with radiofrequency catheter ablation (RFCA) of accessory pathway (AP) and atrial fibrillation (AF) include only short follow-up periods. The aim of this study was to analyze predictors of recurrence of AF in patients after successful RFCA of APs over long term follow-up periods. METHODS: Of the 1,007 patients who underwent non-pharmacological treatment of APs (between the years 1993-2008), data of 100 consecutive patients were retrospectively analyzed (75 men, mean age 43.6 ± 14.7), with the longest period of follow-up (mean 11.3 ± 3.5 years) after successful RFCA of AP. In Group 1, there were 72 patients (54 men, mean age 40.66 ± 13.85 years) without documented episodes of AF after RFCA of AP. Group 2 consisted of 28 patients (21 men, mean age 50.79 ± 14.49 years) with AF episodes despite successful elimination of AP. RESULTS: In univariate analysis, patients from Group 1 were significantly younger at the time of abla-tion than patients from Group 2 (40.66 ± 13.85 vs. 50.79 ± 14.49 years; p = 0.002), had shorter his¬tory of AF episodes (4.11 ± 4.07 vs. 8.25 ± 7.50 years; p = 0.024) and had less frequently documented atrial tachycardia (AT) prior to ablation (3.39 vs. 20.00% years; p = 0.022). In multivariate analysis, the history of AF in years (p = 0.043), was an independent risk factor for AF recurrences. CONCLUSIONS: Older patient age, longer history of AF and AT prior to RFCA of APs identified a sub-group of patients who required additional treatment. In the multivariate analysis, the history of AF in years (p = 0.043) was a risk factor for AF recurrence.