Contact allergy to subcutaneous implantable cardioverter defibrillator in a child with Brugada syndrome.

Allergic reactions to components of cardiac implantable electronic devices are rare and often go undiagnosed, which can lead to a misdiagnosis of device infection. Contact allergy to subcutaneous implantable cardioverter defibrillator (S-ICD) is extremely rare. In this report, we present a case of cobalt-related contact allergy in a pediatric patient with Brugada syndrome who underwent S-ICD implantation.

Exercise-induced type 1 Brugada pattern in a child.

The exercise stress testing may unmask the type 1 Brugada pattern on the surface electrocardiogram in a portion of patients with Brugada syndrome. The occurrence of the type 1 Brugada pattern during an exercise test in pediatric patients is not common. Consequently, the diagnostic yield of the exercise test in this population is still to be explored. We present a case of exercise-induced type 1 Brugada pattern in a 12-year-old child with episodes of palpitations and discuss the available evidence on the role of the exercise stress test in the diagnosis and risk stratification of patients with Brugada syndrome.

Single-Chamber and Dual-Chamber Pacemaker Devices in Adults with Moderate and Complex Congenital Heart Disease: A Single Tertiary Referral Center Experience.

The number of device implantation procedures has increased in adult patients with congenital heart disease (ACHD). Despite significant improvements in materials and implantation techniques, these patients are exposed to higher risk of device related complications than general population. Herein, we describe our single tertiary referral center experience on transvenous pacemaker (PM) implantation and follow-up in adult patients with moderate and complex congenital heart disease (CHD) as limited data are available on long-term outcome. We considered all adults with moderate and complex CHD aged more than 16 years who underwent transvenous single-chamber and dual-chamber PM implant for sinus node dysfunction or atrioventricular block between January 2013 to December 2022 at our Unit. Seventy-one ACHD patients were included in the study (mean age 38.6 ± 15.2 years, 64% with moderate CHD, 36% with complex CHD). Among 32 patients implanted with a dual chamber PM (DDD PM), 4 devices were reprogrammed in VDD mode, 3 in VVI and 2 in AAI mode during follow-up because of lead dysfunction or permanent atrial arrhythmia. In addition, 26 patients had a single chamber PM (AAI or VVI PM) and 13 patients had single-lead pacing system with a free-floating atrial electrode pair (VDD PM). Just one of 13 single-lead VDD PM was reprogrammed in VVI mode due to a low atrial sensing. In DDD PM group, 10 re-interventions were needed due to lead dysfunction (8 cases) and lead-related infective endocarditis (2 cases). Only 3 patients in the single-lead PM group developed lead dysfunction with 2 re-interventions needed, but no infective endocarditis was reported. The rate of long-term complications is high in moderate and complex ACHD with transvenous PM devices, and it is mainly lead-related. In our experience, the less leads implanted, the less complications will occur. Considering the heterogeneity of the ACHD population, transvenous single-chamber or dual-chamber PM device implantation should always be tailored on the single patient, balancing risks and benefits in this complex population.

Triple Antiarrhythmic Therapy in Newborns with Refractory Atrioventricular Reentrant Tachycardia.

Atrioventricular reentrant tachycardia (AVRT) is the most common form of supraventricular tachycardia in newborns. AVRT is sometimes refractory to conventional antiarrhythmic therapy. We describe our experience about the use of the triple combination of flecainide + propranolol + amiodarone as third-line regimen for refractory and recurrent AVRT in newborns. We considered a series of 14 patients who had failed both first-line and second-line therapy and were treated using the combination of flecainide + propranolol + amiodarone. Transoesophageal electrophysiologic study (TES) was performed to test the effectiveness of medical therapy during hospitalization and to try to reduce the amount of therapy, after amiodarone wash-out, before 1 year of age. TES was repeated at 1 year of age to test the spontaneous resolution of the arrhythmia after treatment discontinuation. Rhythm control was achieved in all 14 patients. At a mean age of 9.3 ± 2 months, AVRT was not inducible by TES in 11/12 amiodarone-free patients. At a mean age of 14.1 ± 3 months, AVRT was still inducible in 7/12 patients after interrupting the entire antiarrhythmic therapy (58.3%). Triple combination was effective as third-line option to suppress AVRT refractory to single and double antiarrhythmic therapy, with no significant adverse events. Our experience suggests that triple therapy could be maintained for a short-term treatment, discontinuing amiodarone before 1 year of age to avoid long-term side effects. Newborns who needed triple therapy appear to have a lower chance of accessory pathway disappearance at 1 year of age. TES could be useful for risk stratification of recurrences at the time of drug discontinuation in infants considered to be at higher risk of recurrent AVRT.

Implantable Loop Recorder with Long Sensing Vector: Safety, Acceptability, and Sensing Performance in Pediatric Patients.

Implantable loop recorders (ILRs) are effective tools for detecting arrhythmias by long-term continuous heart rhythm monitoring. Benefits have been demonstrated even in pediatric patients. ILR with a long sensing vector has recently been designed to improve signal quality in terms of P wave visibility and R wave amplitude. However, there are no data on its use in pediatric patients. We considered a series of pediatric patients implanted with a long sensing vector ILR. Sensing performance, including R wave amplitude and P wave visibility, device-related complications, and diagnostic yield were collected. During follow-up, each patient guided by his/her parents/guardians was also asked to complete a brief questionnaire to assess patient acceptability of the device. Twenty-five consecutive pediatric patients (mean age 11.3 ± 3.5 years, 72% male) were enrolled. The insertion success rate was 100% on the first attempt with no complications. The median amplitude of the R wave was 1.15 mV (interquartile range, 1.01-1.42) with no significant differences between patients aged ≤ or > 10 years (p = 0.726) and between female and male (p = 0.483). P wave was classified as 'always visible' in 24/25 patients (96%). ILR was generally well accepted and tolerated by all involved patients. During a median follow-up of 297 days (117-317), we achieved in 5 patients a correlation between symptoms and rhythm disorders (20%) and ruled out significant arrhythmias in 6 symptomatic children (24%). Long sensing vector ILR showed to be well accepted, with good signal quality and an excellent safety profile even in pediatric patients.

Echocardiographic probability of pulmonary hypertension: a validation study.

BACKGROUND: According to current guidelines, the diagnosis of pulmonary hypertension (PH) relies on echocardiographic probability followed by right heart catheterisation (RHC). How echocardiography predicts PH recently redefined by mean pulmonary arterial pressure (mPAP) >20 mmHg instead of ≥25 mmHg and pulmonary vascular disease defined by pulmonary vascular resistance (PVR) ≥3 or >2 WU has not been established. METHODS: A total of 278 patients referred for PH underwent comprehensive echocardiography followed by RHC. 15 patients (5.4%) were excluded because of insufficient quality echocardiography. RESULTS: With PH defined by mPAP >20 mmHg, 23 patients had no PH, 146 had pre-capillary PH and 94 had post-capillary PH. At univariate analysis, maximum tricuspid regurgitation velocity (TRV) 2.9-3.4 m·s-1, left ventricle (LV) eccentricity index >1.1, right ventricle outflow tract acceleration time (RVOT-AT) <105 ms or notching, RV/LV basal diameter >1 and pulmonary artery diameter predicted PH, whereas inferior vena cava diameter and right atrial area did not. At multivariable analysis, only TRV ≥2.9 m·s-1 independently predicted PH. Additional independent prediction of PVR ≥3 WU was offered by LV eccentricity index >1.1, and RVOT-AT <105 ms and/or notching, but with no improvement of optimal combination of specificity and sensitivity or positive prediction. CONCLUSIONS: Echocardiography as recommended in current guidelines can be used to assess the probability of redefined PH in a referral centre. However, the added value of indirect signs is modest and sufficient quality echocardiographic signals may not be recovered in some patients.

The paradox of pulmonary arterial hypertension in Italy in the COVID-19 era: is risk of disease progression around the corner?

OBJECTIVE: The coronavirus disease 2019 (COVID-19) outbreak has led to significant restrictions on routine medical care. We conducted a multicentre nationwide survey of patients with pulmonary arterial hypertension (PAH) to determine the consequences of governance measures on PAH management and risk of poor outcome in patients with COVID-19. MATERIALS AND METHODS: The present study, which included 25 Italian centres, considered demographic data, the number of in-person visits, 6-min walk and echocardiographic test results, brain natriuretic peptide/N-terminal pro-brain natriuretic peptide test results, World Health Organization functional class assessment, presence of elective and non-elective hospitalisation, need for treatment escalation/initiation, newly diagnosed PAH, incidence of COVID-19 and mortality rates. Data were collected, double-checked and tracked by institutional records between March 1 and May 1, 2020, to coincide with the first peak of COVID-19 and compared with the same time period in 2019. RESULTS: Among 1922 PAH patients, the incidences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and COVID-19 were 1.0% and 0.46%, respectively, with the latter comparable to that in the overall Italian population (0.34%) but associated with 100% mortality. Less systematic activities were converted into more effective remote interfacing between clinicians and PAH patients, resulting in lower rates of hospitalisation (1.2% versus 1.9%) and related death (0.3% versus 0.5%) compared with 2019 (p<0.001). A high level of attention is needed to avoid the potential risk of disease progression related to less aggressive escalation of treatment and the reduction in new PAH diagnoses compared with 2019. CONCLUSION: A cohesive partnership between healthcare providers and regional public health officials is needed to prioritise PAH patients for remote monitoring by dedicated tools.

Risk Reduction and Hemodynamics with Initial Combination Therapy in Pulmonary Arterial Hypertension.

Rationale: An initial oral combination of drugs is being recommended in pulmonary arterial hypertension (PAH), but the effects of this approach on risk reduction and pulmonary vascular resistance (PVR) are not known.Objectives: To test the hypothesis that a low-risk status would be determined by the reduction of PVR in patients with PAH treated upfront with a combination of oral drugs.Methods: The study enrolled 181 treatment-naive patients with PAH (81% idiopathic) with a follow-up right heart catheterization at 6 months (interquartile range, 144-363 d) after the initial combination of endothelin receptor antagonist + phosphodiesterase-5 inhibitor drugs and clinical evaluation and risk assessments by European guidelines and Registry to Evaluate Early and Long-Term PAH Disease Management scores.Measurements and Main Results: Initial combination therapy improved functional class and 6-minute-walk distance and decreased PVR by an average of 35% (median, 40%). One-third of the patients had a decrease in PVR <25%. This poor hemodynamic response was independently predicted by age, male sex, pulmonary artery pressure and cardiac index, and at echocardiography, a right/left ventricular surface area ratio of greater than 1 associated with low tricuspid annular plane systolic excursion of less than 18 mm. A low-risk status at 6 months was achieved or maintained in only 34.8% (Registry to Evaluate Early and Long-Term PAH Disease Management score) to 43.1% (European score) of the patients. Adding criteria of poor hemodynamic response improved prediction of a low-risk status.Conclusions: A majority of patients with PAH still insufficiently improved after 6 months of initial combinations of oral drugs is identifiable at initial evaluation by hemodynamic response criteria added to risk scores.

Subcutaneous finger cardioverter-defibrillator in low weight paediatric patients: a case series.

Placement of traditional transvenous implantable cardioverter defibrillator (ICD) system in low-weight children is often difficult because of their vessel size, the elevated risk of lead malfunction and failure, children's growth and various anatomic constraints, creating the need for alternative solutions. Subcutaneous array leads combined with an abdominally placed ICD device can minimize the surgical approach. In this case series, we analyse the data behind indications for subcutaneous finger cardioverter defibrillator (SFCD) and discuss the preliminary clinical experience in low-weight children. We considered 4 consecutive children (mean age 3.9 years, range 3-5.5 years, mean body weight 17.6 Kg, range 14-23 Kg) who underwent SFCD implant from April 2016 to August 2020. All patients showed a good compliance to the device system with no complications (infections or skin erosions). No patients experienced in the observation period (mean time 44.5±21.5 months) sustained ventricular arrhythmias requiring shocks. No inappropriate shocks released by the device occurred. No significant changes were observed in LET (lowest energy tested) performed around 24 months of follow-up. All patients showed a good compliance and stable atrio-ventricular sensing and pacing thresholds. In smaller children in whom a transvenous approach is not feasible or not possible for anatomic reasons, the SFCD appears to be a safe method to prevent SCD with little surgical trauma and preservation of an intact vascular system, providing an adequate bridge to transvenous ICD or subcutaneous ICD implant late in the life.

Cardiac resynchronization therapy-defibrillator implantation guided by electroanatomic mapping in a young adult patient with congenital heart disease.

Cardiac resynchronization therapy-defibrillator (CRT-D) implantation is a therapeutic option for adult patients with congenital heart disease (CHD), bundle branch block, reduced ejection fraction and symptoms of heart failure. A new implantation approach guided by the electroanatomic mapping (EAM) has been developed to overcome some issues of the standard technique: non-responder patients, high x-ray exposure and use of iodinated contrast medium for coronary sinus angiography. This approach has not been previously described in the CHD population. We report a case of EAM-guided approach for CRT-D implantation in a young adult patient with CHD.

Wearable cardioverter-defibrillator (life-vest): A feasible bridging treatment in adult congenital heart disease.

BACKGROUND: Wearable cardioverter-defibrillators (WCDs) are currently used in patients at temporarily heightened risk for sudden cardiac death (SCD) who are temporarily unable to receive an implantable cardioverter-defibrillator (ICD). WCD can safely record and terminate life-threatening arrhythmias through a non-invasive electrode-based system. The current clinical indications for WCD use are varied and keep evolving as experience with this technology increases. METHODS: We reviewed and explored the data behind indications for WCD use and discuss its usefulness in congenital heart disease (CHD) patients. RESULTS: We considered 8 consecutive patients (mean age 35.25 years, range 18-51 years, average duration of WCD use 4 months, range 3-6 months) with complex CHD, in which a WCD was used between June 2018 and January 2022. No sustained ventricular arrhythmias requiring shocks were recorded in the observation period. No inappropriate shocks were recorded. All the patients showed a good compliance and a very high mean wear time per day (21.2 ± 1 h a day). Four patients implanted a permanent device (3 CRT-D, 1 ICD), three underwent cardiac surgery at the end of the WCD period and one is still on the waiting list for the operation. CONCLUSIONS: Larger trial could confirm the possible conceivable benefit from an extended use of the WCD in certain populations with complex CHD as in our case series, especially in patients with life-treating ventricular arrhythmias waiting for surgery for residual cardiac defects or in the early phases following the surgical/hemodynamic interventions, patients with tachycardiomyopathy expected to improve after the arrhythmias are removed and patients awaiting implantation of an ICD at high risk due to active infection.

Retrieval of a leadless transcatheter pacemaker from the right pulmonary artery: A case report.

This case report describes a procedure of retrieval of a leadless transcatheter pacemaker from the right pulmonary artery 3 days after device implantation. An 80-year-old man affected by ischemic cardiomyopathy and sinus node dysfunction was implanted with a leadless transcatheter pacemaker in the low septum of the right ventricle. Three days after the procedure, the leadless pacemaker migrated into a side branch of the right pulmonary artery. The device was successfully removed using two snares hooked to a tine via the proximal retrieval feature.

A frightening giant QRS complex in a 3-months-old infant.

A 3-months-old infant was urgently admitted for drowsiness and lack of appetite started 24 h before. The ECG showed sinus rhythm with a prolonged AV interval (200 ms) and very large QRS complexes (280 ms) due to Flecainide overdosing following incorrectly administration for poor communication between parents resulted in both giving a dose to the infant. Flecainide serum level was 1.2µg/ml, confirming the diagnosis of an accidental drug intoxication. The patient started continue hydration with a close monitoring. Three hours later a significant narrowing of the QRS complex (150 ms) was observed, then over the following 24 h, the QRS almost completely normalized.

Right ventricular-arterial uncoupling independently predicts survival in COVID-19 ARDS.

AIM: To investigate the prevalence and prognostic impact of right heart failure and right ventricular-arterial uncoupling in Corona Virus Infectious Disease 2019 (COVID-19) complicated by an Acute Respiratory Distress Syndrome (ARDS). METHODS: Ninety-four consecutive patients (mean age 64 years) admitted for acute respiratory failure on COVID-19 were enrolled. Coupling of right ventricular function to the pulmonary circulation was evaluated by a comprehensive trans-thoracic echocardiography with focus on the tricuspid annular plane systolic excursion (TAPSE) to systolic pulmonary artery pressure (PASP) ratio RESULTS: The majority of patients needed ventilatory support, which was noninvasive in 22 and invasive in 37. There were 25 deaths, all in the invasively ventilated patients. Survivors were younger (62 ± 13 vs. 68 ± 12 years, p = 0.033), less often overweight or usual smokers, had lower NT-proBNP and interleukin-6, and higher arterial partial pressure of oxygen (PaO2)/fraction of inspired O2 (FIO2) ratio (270 ± 104 vs. 117 ± 57 mmHg, p < 0.001). In the non-survivors, PASP was increased (42 ± 12 vs. 30 ± 7 mmHg, p < 0.001), while TAPSE was decreased (19 ± 4 vs. 25 ± 4 mm, p < 0.001). Accordingly, the TAPSE/PASP ratio was lower than in the survivors (0.51 ± 0.22 vs. 0.89 ± 0.29 mm/mmHg, p < 0.001). At univariate/multivariable analysis, the TAPSE/PASP (HR: 0.026; 95%CI 0.01-0.579; p: 0.019) and PaO2/FIO2 (HR: 0.988; 95%CI 0.988-0.998; p: 0.018) ratios were the only independent predictors of mortality, with ROC-determined cutoff values of 159 mmHg and 0.635 mm/mmHg, respectively. CONCLUSIONS: COVID-19 ARDS is associated with clinically relevant uncoupling of right ventricular function from the pulmonary circulation; bedside echocardiography of TAPSE/PASP adds to the prognostic relevance of PaO2/FIO2 in ARDS on COVID-19.

The role of 3D-high definition mapping systems in treating postoperative drug-resistant intra-atrial reentrant tachycardia.

We report the case of a patient with recurrent episodes of postoperative intra-atrial reentrant tachycardia occurring after surgical patch closure of a sinus venosus atrial septal defect (SVASD). Arrhythmic episodes, as usually reported in scar-related arrhythmias, were resistant to antiarrhythmic therapy and worsened patient's quality of life. Therefore, we decided to perform an intracardiac electrophysiology study using a 3D-high definition mapping system to identify and treat the precise arrhythmic substrate with radiofrequency ablation. There is a growing evidence that this technique represents a valid therapeutic option in postoperative arrhythmias refractory to medical treatment in patients with repaired congenital heart disease.

Invasive and Noninvasive Evaluation for the Diagnosis of Pulmonary Hypertension: How to Use and How to Combine Them.

The etiologic diagnosis of pulmonary hypertension (PH) may be very challenging. Right-heart catheterization (RHC) in isolation cannot classify a precapillary PH patient into group 1, 3, 4, or 5. Moreover, RHC may be not sufficient for reaching a definitive differential diagnosis of precapillary or postcapillary PH if hemodynamic data are not integrated in clinical context and combined with information gleaned from noninvasive imaging. Therefore, only the integration of risk factors, clinical evaluation, invasive and noninvasive tests allows the physician to distinguish between different forms of PH.

Echocardiographic assessment of right ventricular contractile reserve in healthy subjects.

BACKGROUND: Exercise-induced increase in pulmonary artery systolic pressure (PASP) as a possible measure of right ventricular (RV) contractile reserve has been shown to predict survival in severe pulmonary hypertension. However, RV contractile reserve can also be measured by changes in stroke volume (SV), tricuspid annular plane systolic excursion (TAPSE), or tricuspid annular systolic velocity (S'). The limits of normal values and the functional significance of these changes in healthy subjects are not well known. METHODS: In this prospective study, 90 healthy subjects (45 male, mean age 39 ± 13 years) underwent exercise stress echocardiography with measurement of TAPSE, S', TAPSE/PASP, SV, and PASP at rest and peak exercise. Maximum and minimum normal values were reported for all indices. RESULTS: Normal values of exercise-induced changes (Δ) were 4 to 10 mm for TAPSE, 6 to 14 cm/s for S', 12 to 57 mm Hg for PASP, 0 to 96 mL for SV, and -1.2 to 0 mm/mm Hg for TAPSE/PASP. At peak exercise, women showed lower ΔTAPSE/PASP, ΔPASP, ΔS', and ΔSV, but higher TAPSE/PASP than men. Aging was associated with decreased ΔTAPSE/PASP, ΔTAPSE, ΔS', ΔPASP, and ΔSV. In addition, ΔS', ΔTAPSE/PASP, ΔPASP, and ΔSV, but not ΔTAPSE, were directly correlated with maximum workload. CONCLUSIONS: Our results provide age- and sex-related limits of normal for RV contractile reserve as assessed by exercise stress echocardiography and demonstrate that RV systolic function indices (PASP, TAPSE, S', and TAPSE/PASP) correlate with maximum exercise capacity.

Allelic Complexity in Long QT Syndrome: A Family-Case Study.

Congenital long QT syndrome (LQTS) is associated with high genetic and allelic heterogeneity. In some cases, more than one genetic variant is identified in the same (compound heterozygosity) or different (digenic heterozygosity) genes, and subjects with multiple pathogenic mutations may have a more severe disease. Standard-of-care clinical genetic testing for this and other arrhythmia susceptibility syndromes improves the identification of complex genotypes. Therefore, it is important to distinguish between pathogenic mutations and benign rare variants. We identified four genetic variants (KCNQ1-p.R583H, KCNH2-p.C108Y, KCNH2-p.K897T, and KCNE1-p.G38S) in an LQTS family. On the basis of in silico analysis, clinical data from our family, and the evidence from previous studies, we analyzed two mutated channels, KCNQ1-p.R583H and KCNH2-p.C108Y, using the whole-cell patch clamp technique. We found that KCNQ1-p.R583H was not associated with a severe functional impairment, whereas KCNH2-p.C108Y, a novel variant, encoded a non-functional channel that exerts dominant-negative effects on the wild-type. Notably, the common variants KCNH2-p.K897T and KCNE1-p.G38S were previously reported to produce more severe phenotypes when combined with disease-causing alleles. Our results indicate that the novel KCNH2-C108Y variant can be a pathogenic LQTS mutation, whereas KCNQ1-p.R583H, KCNH2-p.K897T, and KCNE1-p.G38S could be LQTS modifiers.

Right heart and pulmonary vessels structure and function.

The right ventricle (RV) can be described in terms of 3 components: the inlet, the apex, and the infundibulum. In the normal adult, the RV shows an arrangement suited for pumping blood against low resistance, with a mass about one sixth that of left ventricle (LV) mass, and a larger volume than the LV. The RV is able to manage a progressive increase in the afterload by increasing contractility and remodeling. The gold standard measurement of contractility is maximal elastance (Emax), or the ratio between end-systolic pressure (ESP) and end-systolic volume (ESV), and the best measurement of afterload is arterial elastance (Ea), or the ratio between ESP and stroke volume (SV). The ratio Emax/Ea defines RV-arterial coupling. The optimal energy transfer from the RV to the pulmonary circulation is measured at Emax/Ea ratios of 1.5-2. In the presence of pulmonary hypertension, the SV/ESV ratio may be an acceptable surrogate of Emax/Ea. The right atrium (RA) has 3 anatomical components: the appendage, the venous part, and the vestibule. It is a dynamic structure having different functions: reservoir, conduit, and booster pump function. In case of increased afterload, the RA is enlarged, denoting high RA pressure, as a consequence of elevated RV diastolic pressure. RA area is a strong predictor of adverse clinical outcome in pulmonary arterial hypertension. In patients with severe pulmonary hypertension, in several congenital heart diseases, and in Eisenmenger syndrome, symptoms and prognosis are greatly dependent on RV function and its ability to adapt to a chronic increase in afterload.