The diagnostic and therapeutic challenge of atrial flutter in children: a case report

BACKGROUND

Palpitations represent a common cause for consultation in the pediatric Emergency Department (ED). Unlike adults, palpitations in children are less frequently dependent from the heart, recognizing other causes.

CASE PRESENTATION

A 11-year-old male came to our pediatric ED for epigastric pain, vomiting and palpitations. During the previous 6 month the patient was affected by SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus). Electrocardiogram (ECG) revealed supraventricular tachycardia. Therefore, adenosine was administered unsuccessfully. The administration of adenosine, however, allowed us to make diagnosis of atypical atrial flutter. Multiple attempts at both electrical cardioversion, transesophageal atrial overdrive, and drug monotherapy were unsuccessful in our patient. Consequently, a triple therapy with amiodarone, flecainide, and beta-blocker was gradually designed to control the arrhythmic pattern with the restoration of a left upper atrial rhythm. There was not any evidence of sinus rhythm in the patient clinical history.

CONCLUSIONS

The present study underlines the rarity of this type of dysrhythmia in childhood and the difficulties in diagnosis and management, above all in a patient who has never showed sinus rhythm. Raising awareness of all available treatment options is essential for a better management of dysrhythmia in children.

Effect of Digitalis on ICD or CRT-D Recipients: A Systematic Review and Meta-Analysis

BACKGROUND

Digitalis has been widely utilized for heart failure therapy and several studies have demonstrated an association of digitalis and adverse outcome events in patients receiving implantable cardioverter defibrillators (ICDs) or cardiac resynchronization therapy defibrillators (CRT-Ds). Hence, we conducted this meta-analysis to assess the effect of digitalis on ICD or CRT-D recipients.

METHODS

We systematically retrieved relevant studies using the Cochrane Library, PubMed, and Embase database. A random effect model was used to pool the effect estimates (hazard ratios (HRs) and 95% confidence intervals (CIs)) when the studies were of high heterogeneity, otherwise a fixed effect model was used.

RESULTS

Twenty-one articles containing 44,761 ICD or CRT-D recipients were included. Digitalis was associated with an increased rate of appropriate shocks (HR = 1.65, 95% CI: 1.46-1.86, p < 0.001) and a shortened time to first appropriate shock (HR = 1.76, 95% CI: 1.17-2.65, p = 0.007) in ICD or CRT-D recipients. Furthermore, the all-cause mortality increased in ICD recipients with digitalis therapy (HR = 1.70, 95% CI: 1.34-2.16, p < 0.01), but the all-cause mortality was unchanged in CRT-D recipients (HR = 1.55, 95% CI: 0.92-2.60, p = 0.10) or patients who received ICD or CRT-D therapy (HR = 1.09, 95% CI: 0.80-1.48, p = 0.20). The sensitivity analyses confirmed the robustness of the results.

CONCLUSION

ICD recipients with digitalis therapy may tend to have higher mortality rates, but digitalis may not be associated with the mortality rate of CRT-D recipients. Further studies are required to confirm the effects of digitalis on ICD or CRT-D recipients.

Impact of signal-averaged electrocardiography findings on appropriate shocks in prophylactic implantable cardioverter defibrillator patients with nonischemic systolic heart failure

BACKGROUND

Appropriate shock therapy is associated with subsequent all-cause death in heart failure (HF) patients who receive an implantable cardioverter defibrillator (ICD) for the primary prevention of sudden cardiac death. To evaluate the impact of signal-averaged electrocardiography (SAECG) findings on appropriate shocks in prophylactic ICD patients with nonischemic systolic HF.

METHODS

We studied 86 patients with nonischemic HF and a left ventricular ejection fraction ≤ 35% who underwent new ICD implantation for the primary prevention of sudden cardiac death. We excluded patients who had a previously implanted permanent pacemaker and patients who received cardiac resynchronization therapy with an ICD. SAECG was performed before implantation. Abnormal SAECG findings were defined if 2 of the following 3 conditions were identified: filtered QRS duration (fQRS) ≥ 114 ms, root-mean-square voltage during the last 40 ms of the fQRS (RMS 40) < 20 μV, and duration of the low-amplitude potentials < 40 μV (LAS 40) > 38 ms; additionally, patients with a QRS complex ≥ 120 ms who met both the RMS 40 and LAS 40 criteria were also considered to have abnormal SAECG findings. The primary outcome was the first occurrence of appropriate shock after implantation of the ICD. The secondary outcomes were the first occurrence of inappropriate shock and all-cause mortality.

RESULTS

Forty-two patients met the criteria for abnormal SAECG findings (49%). During a median follow-up period of 61 months, 17 patients (20%) died, 24 (28%) received appropriate shock therapy, and 19 (22%) received inappropriate shock therapy. There was a significantly higher incidence of appropriate shocks in patients with abnormal SAECG findings than in those with normal SAECG findings (log-rank test, p = 0.025). Multivariate analysis revealed that abnormal SAECG findings were independently associated with the occurrence of appropriate shock (hazard ratio 2.67, 95% confidential interval 1.14-6.26). However, abnormal SAECG findings were not related to inappropriate shock. There was no difference in the incidence of all-cause death between patients with abnormal and normal SAECG findings.

CONCLUSIONS

Our results suggest that abnormal SAECG findings are associated with a high probability of appropriate shocks in prophylactic ICD patients with nonischemic systolic HF.

Digoxin in patients with advanced heart failure and sinus rhythm submitted to cardiac resynchronization therapy- is there any benefit?

ABSTRACT

Digoxin use in patients with heart failure with reduced ejection fraction (HFrEF) and sinus rhythm remains controversial. We aimed to assess the prognostic impact of digoxin in patients in sinus rhythm submitted to cardiac resynchronization therapy (CRT).Retrospective study including 297 consecutive patients in sinus rhythm, with advanced HFrEF submitted to CRT. Patients were divided into two groups - with digoxin (DG) and without digoxin (NDG). During a mean follow-up of 4.9 ± 3.4 years we evaluated the impact of digoxin on the composite endpoint defined as cardiovascular hospitalization, progression to heart transplantation and all-cause mortality.Previous to CRT, 104 patients (35%) were chronically under digoxin and 193 patients (65%) without digoxin treatment. The 2 groups did not differ significantly regarding HF functional class, HF aetiology, QRS and baseline left ventricular ejection fraction (LVEF). The proportion of responders to CRT was similar in both groups (54% in DG vs 56% in NDG, p=0.78). During the long term follow up period, the primary endpoint occurred in a higher proportion in DG patients (67 vs 48%, p=0.002). After adjustment for potential confounders, digoxin use remained as an independent predictor of the composite endpoint of CV hospitalization, heart transplantation and all-cause mortality (HR = 1.58, CI 95 [1.01 - 2.46], p = 0.045).In conclusion, in patients in sinus rhythm with HFrEF submitted to CRT, digoxin use was associated to CV hospitalization, progression to heart transplant and all-cause mortality.

Association of digoxin therapy with case fatality rate in acute pulmonary embolism

OBJECTIVE

Despite wide usage of digoxin for various diseases in cardiology practice, its benefit is controversial and moreover it had been associated with unfavorable outcomes in some previous studies. The aim of this present study was to demonstrate whether digoxin usage was related with worse outcomes or not in patients with acute pulmonary embolisms.

METHODS

A total number of 1215 patients retrospectively enrolled for the study. Basic demographic features, pulmonary embolism severity index (PESI) scores, laboratory parameters and medications of patients who had been diagnosed with acute pulmonary embolism were recorded. Short (30 days) and long-term mortality were reported as the clinical outcomes.

RESULTS

Total mortality was 15.4% in the study population and 78 of these subjects died within the first 30 days. The frequency of digoxin treatment was 8% and most of these patients were prior users. According to the binary logistic regression analyses the PESI score, right ventricle (RV) diastolic diameter, systolic pulmonary arterial pressure (sPAP), brain natriuretic peptide (BNP), troponin and digoxin therapy (odds ratio, OR: 2.82 95% confidence interval, CI: 1.39-8.31, P = 0.03) were found as independent predictors of short-term mortality. Beside these findings; sPAP, PESI score, RV diastolic diameter and digoxin therapy (hazard ratio, HR: 2.11 95%CI: 1.22-7.31, P = 0.03) were determined as independent predictors of long-term mortality in Cox regression analyses. In subgroup analysis, we determined significantly greater increase in short-term mortality with use of digoxin among patients who had chronic renal disease, among patients under thrombolytic therapy and under high dosage of digoxin therapy and among female patients.

CONCLUSION

Digoxin has been used extensively for decades in the treatment of heart failure and arrhythmias despite some controversies over its benefit. For the first time in the literature, we have demonstrated independent association of digoxin therapy with short-term and long-term mortality in patients with acute pulmonary embolism.

Digitalis Therapy and Risk of Recurrent Ventricular Tachyarrhythmias and ICD Therapies in Atrial Fibrillation and Heart Failure

OBJECTIVE

This study sought to assess the impact of treatment with digitalis on recurrences of ventricular tachyarrhythmias in implantable cardioverter defibrillator (ICD) recipients with atrial fibrillation (AF) and heart failure (HF).

BACKGROUND

The data regarding outcomes of digitalis therapy in ICD recipients are limited.

METHODS

A large retrospective registry was used, including consecutive ICD recipients with episodes of ventricular tachyarrhythmia between 2002 and 2016. Patients treated with digitalis were compared to patients without digitalis treatment. The primary prognostic outcome was first recurrence of ventricular tachyarrhythmia at 5 years. Kaplan-Meier and multivariable Cox regression analyses were applied.

RESULTS

A total of 394 ICD recipients with AF and/or HF was included (26% with digitalis treatment and 74% without). Digitalis treatment was associated with decreased freedom from recurrent ventricular tachy-arrhythmias (HR = 1.423; 95% CI 1.047-1.934; p = 0.023). Accordingly, digitalis treatment was associated with decreased freedom from appropriate ICD therapies (HR = 1.622; 95% CI 1.166-2.256; p = 0.004) and, moreover, higher rates of rehospitalization (38 vs. 21%; p = 0.001) and all-cause mortality (33 vs. 20%; p = 0.011).

CONCLUSION

Among ICD recipients suffering from AF and HF, treatment with digitalis was associated with increased rates of recurrent ventricular tachyarrhythmias and ICD therapies. However, the endpoints may also have been driven by interactions between digitalis, AF, and HF.

Outcomes of cardiac resynchronisation therapy in patients with heart failure with atrial fibrillation: a systematic review and meta-analysis of observational studies

Background

Cardiac resynchronisation therapy (CRT) is beneficial in selected patients with heart failure (HF) in normal sinus rhythm (NSR). We sought to evaluate the impact of CRT with or without atrioventricular junction (AVJ) ablation in patients with HF with concomitant atrial fibrillation (AF).

Methods and results

Literature was searched (inception through 30 August 2017) for observational studies that reported outcomes in patients with HF with CRT and AF that reported all-cause and cardiovascular mortality. Thirty-one studies with 83, 571 patients were included. CRT did not decrease mortality compared with internal cardioverter defibrillator or medical therapy alone in patients with HF and AF with indications for CRT (OR: 0.851, 95% CI 0.616 to 1.176, p=0.328, I2=86.954). CRT-AF patients had significantly higher all-cause and cardiovascular mortality than CRT-NSR patients ([OR: 1.472, 95% CI 1.301 to 1.664, p=0.000] and [OR: 1.857, 95% CI 1.350 to 2.554, p=0.000] respectively). Change in left ventricular ejection fraction was not different between CRT patients with and without AF (p=0.705). AVJ ablation, however, improved all-cause mortality in CRT-AF patients when compared with CRT-AF patients without AVJ ablation (OR: 0.485, 95% CI 0.247 to 0.952, p=0.035). With AVJ ablation, there was no difference in all-cause mortality in CRT-AF patients compared with CRT-NSR patients (OR: 1.245, 95% CI 0.914 to 1.696, p=0.165).

Conclusion

The results of our meta-analysis suggest that AF was associated with decreased CRT benefits in patients with HF. CRT, however, benefits patients with AF with AVJ ablation.