Effect of dispersive electrode position (anterior vs. posterior) in epicardial radiofrequency ablation of ventricular wall: A computer simulation study.

An epicardial approach is often used in radiofrequency (RF) catheter ablation to ablate ventricular tachycardia when an endocardial approach fails. Our objective was to analyze the effect of the position of the dispersive patch (DP) on lesion size using computer modeling during epicardial approach. We compared the posterior position (patient's back), commonly used in clinical practice, to the anterior position (patient's chest). The model considered ventricular wall thicknesses between 4 and 8 mm, and electrode insertion depths between .3 and .7 mm. RF pulses were simulated with 20 W of power for 30 s duration. Statistically significant differences (P < .001) were found between both DP positions in terms of baseline impedance, RF current (at 15 s) and thermal lesion size. The anterior position involved lower impedance (130.8 ± 4.7 vs. 146.2 ± 4.9 Ω) and a higher current (401.5 ± 5.6 vs. 377.5 ± 5.1 mA). The anterior position created lesion sizes larger than the posterior position: 8.9 ± 0.4 vs. 8.4 ± 0.4 mm in maximum width, 8.6 ± 0.4 vs. 8.1 ± 0.4 mm in surface width, and 4.5 ± 0.4 vs. 4.3 ± 0.4 mm in depth. Our results suggest that: (1) the redirection of the RF currents due to repositioning the PD has little impact on lesion size and only affects baseline impedance, and (2) the differences in lesion size are only 0.5 mm wider and 0.2 mm deeper for the anterior position, which does not seem to have a clinical impact in the context of VT ablation.

The Association Between Ascending Aortic and Left Ventricular Dimensions in Patients After Aortic Valve Replacement.

INTRODUCTION: Aortic valve replacement (AVR) is often recommended for patients with severe aortic stenosis or chronic aortic regurgitation. These conditions result in remodeling of the left ventricle, including increased interstitial fibrosis that may persist even after AVR. These structural changes impact left ventricular (LV) mechanics, causing compromised LV diameter to occur earlier than reduced LV ejection fraction (LVEF). The aim of this study was to examine the effect of left ventricular end-diastolic diameter (LVEDD) and its role in aortic expansion one year after AVR. METHODS: Sixty-three patients who underwent AVR were evaluated. All patients underwent standard transthoracic echocardiography, which included measurements of the ascending aorta, aortic root, LVEF, and LVEDD before the surgery and one year postoperatively. Correlations between these variables were calculated. RESULTS: All patients underwent AVR with either a mechanical or biological prosthetic aortic valve. Following AVR, there was a significant decrease in the dimensions of the ascending aorta and aortic root (both P=0.001). However, no significant changes were observed in LVEDD and LVEF. Correlations were found between the preoperative ascending aortic size and the preoperative and one-year postoperative LVEDD (r=0.419, P=0.001 and r=0.320, P=0.314, respectively). Additionally, there was a correlation between the postoperative ascending aortic size and the preoperative and one-year postoperative LVEDD (r=0.320, P=0.003 and r=0.136, P=0.335, respectively). CONCLUSION: The study findings demonstrate a significant correlation between the size of the aortic root and ascending aorta, before and after AVR. Additionally, a notable correlation was observed between postoperative LVEDD and the size of the aortic root.

[Tratamiento endovascular exitoso de aneurisma del ventrículo izquierdo en un paciente pediátrico].

BACKGROUND: Aneurysms and diverticula of the left ventricle are rare entities in childhood, with a prevalence of less than 0.1%. Described since 1886, as a severe and potentially fatal disease if not corrected, mainly due to the presence of associated anomalies and the risk of rupture. OBJETIVE: Present other management options for ventricular diverticula, different from surgical options, using alternative materials that are not used very often in daily practice. METHOD: A detailed description of a case successfully managed with these new treatment modalities. RESULTS: Endovascular management of the left ventricular diverticulum, diagnosed prenatally in the patient presented, was successful after initial failure with surgical management. CONCLUSIONS: Endovascular management of ventricular diverticula, using alternative materials to those commonly used, is an attractive option with satisfactory results in these patients.

Living to Tell the Tale: A First-Person Chronicle of the Development of the Fontan-Kreutzer Procedure.

The current surgical approach for patients with a single ventricle is the culmination of decades of dedicated research and groundbreaking innovation. From 1971 to the present day, a series of incremental advancements have significantly extended the life expectancy of these patients. Since the very beginning, Dr Guillermo Kreutzer and his team have pioneered different techniques with the ultimate goal of improving outcomes for these individuals. This is, narrated by him, the story of how it all began.

Right Ventricular Outflow Tract Reconstruction in Truncus Arteriosus: A 30-Year Two-Center Comparison between Homografts and Bovine Jugular Vein.

INTRODUCTION: Homografts and bovine jugular vein are the most commonly used conduits for right ventricular outflow tract reconstruction at the time of primary repair of truncus arteriosus. METHODS: We reviewed all truncus patients from 1990 to 2020 in two mid-volume centers. Inclusion criteria were primary repair, age under one year, and implantation of either homograft or bovine jugular vein. Kaplan-Meier analysis was used to estimate survival, freedom from reoperation on right ventricular outflow tract, and freedom from right ventricular outflow tract reoperation or catheter intervention. RESULTS: Seventy-three patients met the inclusion criteria, homografts were implanted in 31, and bovine jugular vein in 42. There was no difference in preoperative characteristics between the two groups. There were 25/73 (34%) early postoperative deaths and no late deaths. Follow-up for survivals was 17.5 (interquartile range 13.5) years for homograft group, and 11.5 (interquartile range 8.5) years for bovine jugular vein group (P=0.002). Freedom from reoperation on right ventricular outflow tract at one, five, and 10 years in the homograft group were 100%, 83%, and 53%; and in bovine jugular vein group, it was 100%, 85%, and 50% (P=0.79). There was no difference in freedom from reoperation or catheter intervention (P=0.32). CONCLUSION: Bovine jugular vein was equivalent to homografts up to 10 years in terms of survival and freedom from right ventricular outflow tract reoperation or catheter intervention. The choice of either valved conduit did not influence the durability of the right ventricle-pulmonary artery conduit in truncus arteriosus.

Off-Pump Resection of Giant Intramural Left Ventricular Hydatid Cyst by Pleuropericardial Approach: a Case Report.

Primary cardiac hydatid cyst is a rare and fatal pathology, especially when involving the left ventricular free wall. A 44-year-old male was diagnosed with large intramural left ventricular hydatid cyst with wall thickness of 6 mm at the thinnest point. Cyst was accessed through pleuropericardial approach (left pleura opened, followed by entry into cyst directly through adjacent pericardium without removing the pericardial adhesions) which resulted in easy entry into the cyst, mitigating the risk of mechanical injury. This case report highlights that with detailed evaluation, cardiac hydatidosis can be addressed with off-pump technique, reducing the anaphylaxis risks and cardiopulmonary bypass-related effects.

Replacement of Obstructed Right Ventricle to Pulmonary Artery Conduits: The Modified Peel Operation.

Reconstruction of the right outflow tract with extracardiac conduits has made complete repair of complex cardiac malformations possible. However, reoperation is usually required for a right ventricle-to-pulmonary artery conduit obstruction. We describe a modified peel operation, where the sides and posterior half of the previously placed conduit are preserved, and a prosthetic roof is placed over the conduit remnant. This has been our current technique to manage conduit obstructions. It is a safe operation and to teach residents. This review aims to convey the technical details of each step of this technique.

Tetralogy of Fallot Repair After Neonatal Right Ventricular Outflow Tract Stenting: Initial Multicenter Experience in Argentina.

Initial management of patients with tetralogy of Fallot, unfavorable anatomy, and reduced pulmonary blood flow is controversial and continues to be a clinical challenge. Pulmonary to systemic shunt anastomosis or primary correction in neonates and small infants is associated with higher morbimortality and increased number of reoperations. Initial right ventricle outflow tract stenting palliation has emerged as an attractive alternative. We report our experience in 14 patients operated on with tetralogy of Fallot and previous right ventricle outflow tract stenting from March 2018 to June 2022. All stented patients had pulmonary annulus and main pulmonary artery Z score ≤ -2.5. Surgical outcomes, complications, and mortality at 30 days were evaluated. Patient's age and weight at surgery were 5.9 months (2-17) and 6.1 kg (3.9-8.9), respectively. Stents were completely removed in 57.1% of patients. A transannular patch was placed in 10 patients, 3 patients required a right ventricle to pulmonary artery conduit due to coronary anomalies and in 1 patient, the pulmonary valve was preserved. Length of stay and ventilation time were 13.6 days (5-27) and 44.8 h (6-44), respectively. Mean time for right ventricle outflow tract stent implantation to surgical correction was 4 months (2-16). There was no mortality, and mean follow-up time of this cohort was 23.1 month (1-41). Surgical correction of severe tetralogy of Fallot after right ventricle outflow tract stenting is an effective alternative achievable without an increase in morbidity and mortality. Difficulty in stent extraction is related to the time since implantation. More number of patients and longer follow-up time are needed to confirm these initial results.

Catheter ablation of frequent monomorphic ventricular arrhythmias in Andersen-Tawil syndrome: case report and focused literature review.

BACKGROUND/PURPOSE: Andersen-Tawil syndrome type 1 is a rare autosomal dominant disease caused by a KCNJ2 gene mutation and clinically characterized by dysmorphic features, periodic muscular paralysis, and frequent ventricular arrhythmias (VAs). Although polymorphic and bidirectional ventricular tachycardias are prevalent, PVCs are the most frequent VAs. In addition, a "dominant" morphology with RBBB pattern associated with either superior or inferior axis is seen in most of the patients. Due to the limited efficacy of most antiarrhythmic drugs, catheter ablation (CA) is an alternative in patients with monomorphic VAs. Based on our experience, we aimed to review the arrhythmogenic mechanisms and substrates for VAs, and we analyzed the potential reasons for CA failure in this group of patients. METHODS: Case report and focused literature review. RESULTS: Catheter ablation has been reported to be unsuccessful in all of the few cases published so far. Most of the information suggests that VAs are mainly originated from the left ventricle and probably in the Purkinje network. Although identifying well-established and accepted mapping criteria for successful ablation of a monomorphic ventricular arrhythmia, papillary muscles seem not to be the right target. CONCLUSIONS: More research is needed to understand better the precise mechanism and site of origin of VAs in Andersen-Tawil syndrome patients with this particular "dominant" monomorphic ventricular pattern to establish the potential role of CA.

Early Bidirectional Glenn Procedure as Initial Surgical Palliation for Functionally Univentricular Heart with Common Arterial Trunk.

We report an unusual case of a 2-month-old baby with a diagnosis of common arterial trunk and double outlet right ventricle with a remote type ventricular septal defect. Taking into consideration the physiologic moment and anatomic findings of the patient, we planned and successfully performed a bidirectional Glenn procedure as its first palliative procedure.

Technical Aspects and Common Pitfalls of Norwood With Modified Blalock Taussig Shunt.

The Stage 1 Norwood procedure is the first of 3 stages in the surgical palliation of hypoplastic left heart syndrome and certain other single ventricle lesions with systemic outflow obstruction. In this article, we address some technical aspects and common pitfalls of the Norwood procedure with systemic to pulmonary shunt for HLHS palliation. We report our results with the Norwood with Blalock Taussig shunt in a cohort of 44 patients over a 7-year period in 2 institutions in Argentina. The results of the Norwood procedure have improved significantly through the understanding and refinement of the surgical techniques. Procedures must be technically perfect since residual lesions are poorly tolerated. Norwood with a modified Blalock Taussig shunt can be performed with low mortality and may provide excellent long-term outcomes.

Novel use of reverse double switch operation in failed left ventricular recruitment pathway.

In spite of great advances in staged left ventricle recruitment strategy, some patients do not achieve biventricular circulation nor are candidates for reversal to single-ventricle palliation. We present a case of a successful reverse double switch operation in a patient with failure of left ventricle recruitment and pulmonary hypertension. This strategy provided a one-and-a-half repair with a sub-pulmonary hypoplastic left ventricle that improved the patient's clinical status, becoming a novel alternative in this particular subset of patients.

Surgical Management of The Endomyocardial Fibrosis of Right Ventricle Mimicking Tumor with Recurrent Pulmonary Embolism.

Endomyocardial fibrosis is a neglected tropical disease that leads to restrictive cardiomyopathy. Its etiopathogenis is unclear and involves the progression of 3 stages of the disease. Compared with echocardiography, cardiac magnetic resonance imaging shows better apical visualization of obliteration and thrombus and provides an early diagnosis. However, there is no specific drug therapy, although surgery can increase survival. Therefore, surgical resection of the fibrous and thickened endocardium is recommended for symptomatic patients. The risk of mortality increases as the ratio of endocardial fibrous tissue per body surface rises. The aim of this manuscript is to describe the surgical management of the right-sided endomyocardial fibrosis mimicking tumor with recurrent pulmonary embolism.

Giant Epicardial Cyst Eroding Left Ventricular Wall Mimicking as Simple Pericardial Cyst.

Epicardial cysts are rarer benign tumors than pericardial cysts. There have been few reports on surgical management of epicardial cysts. A 17-year-old normotensive boy presented with chest pain and palpitations, which on evaluation was found to be a mediastinal mass (pericardial cyst). Surgical resection of the cyst via thoracotomy was planned. The cyst was diagnosed as an epicardial cyst intraoperatively. However, due to the epicardial origin of cyst and posterior adhesions, resection was done via midline approach. The base was formed by visceral pericardium and eroding into myocardium of left ventricle, so the resection was concluded with on-pump surgery. In case of erroneous diagnosis or undesirable finding, a safer midline approach with on-pump surgery, as an alternative to minimally invasive approach for complicated epicardial cysts (erosion into ventricle/lying in close proximity to important structures or near to coronary arteries) should be considered.

Left Ventricular Free-Wall Rupture After Late-Admission STEMI.

This case illustrates a rare but catastrophic complication of acute myocardial infarction, ie, acute rupture of the left ventricular free wall. The majority of patients have hemodynamic impairment on arrival, and a high level of suspicion is needed. Point-of-care echocardiogram is valuable for prompt diagnosis. Management is very challenging and is based on fluid infusion, inotropic support, and pericardiocentesis. Emergency coronary artery bypass grafting and ventricular wall suture may be the only definitive treatment available, although in the majority of cases timely treatment is not possible.

Pulmonary atresia with intact ventricular septum: Intended strategies.

OBJECTIVE: Neonatal interventional strategies for pulmonary atresia with intact ventricular septum are based on tricuspid valve hypoplasia and right ventricle-dependent coronary circulation. We sought to evaluate long-term outcomes comparing biventricular (BiV) versus single-ventricle (SV) strategies. METHODS: Retrospective review was performed of 119 patients diagnosed with pulmonary atresia with intact ventricular septum from 1995 to 2018. Descriptive statistics summarized patient characteristics and a multivariable Cox survival model was used to compare treatment strategies. RESULTS: Of 119 patients, 62 (52.1%) were male and 13 (10.9%) had a chromosomal abnormality. BiV was pursued in 53.8% (64 out of 119) and SV in 46.2% (55 out of 119) with median tricuspid valve z scores of -1.59 (interquartile range, -3.03 to 0.21) and -5.12 (interquartile range, -5.60 to -4.06), respectively. The median follow-up was 6 years (interquartile range, 2-15 years). Overall survival at 1, 3, and 10 years was 82.4% (98 out of 119), 80.6% (96 out of 119) and 79.8% (95 out of 119), respectively. End states include 36 (30.3%) BiV, 33 (27.7%) SV, 22 (18.5%) alive without definitive end state, 21 (17.6%) death before end state, 4 (3.4%) 1-and-a-half ventricle, and 3 (2.5%) transplants. No SV were converted to BiV, whereas 4 out of 64 (6.3%) BiV were converted to SV. After adjusting for gender, chromosomal abnormalities, gestational age, and birth weight, SV patients had a significantly higher hazard of mortality (hazard ratio, 9.0; 95% CI, 2.65-30.69; P < .001). Mortality was higher in those with right ventricle-dependent coronary circulation (41.9% [13 out of 31]) compared with those without right ventricle-dependent coronary circulation (7.3% [6 out of 82]) (P < .001). CONCLUSIONS: Pulmonary atresia with intact ventricular septum remains a challenging lesion for those patients on the SV pathway, particularly with right ventricle-dependent coronary circulation.

Preoperative Left Ventricular Global Longitudinal Strain Identifies Aortic Stenosis Patients with Improved Postoperative Recovery of Left Ventricular Geometry: A Prospective Cohort Study.

INTRODUCTION: The left ventricular ejection fraction (LVEF) is commonly used as a marker of aortic stenosis (AS) disease severity and to indicate surgical intervention. However, an LVEF <50% identifies mainly advanced disease. Hence, earlier detection of subclinical LV systolic dysfunction may improve clinical decision-making. The global longitudinal strain (GLS) can identify subclinical systolic dysfunction at earlier stages of AS progression even in the presence of preserved LVEF. To this end, we evaluated the preoperative prognostic significance of the LVGLS to identify patients who will undergo a more extensive postoperative LV reverse remodeling as a surrogate marker for clinical recovery. METHODS: We performed a prospective observational study based on detailed pre- and postoperative 2D transthoracic echocardiographic examinations, including strain analysis with speckle tracking. We screened 60 consecutive patients with severe AS and a preoperative LVEF ≥50% indicated for surgery; 39 patients met the study entry criteria and consented to their participation. RESULTS: The median age was 67 (range 30-79) years; 56.4% were female. At baseline, the GLS was 61.64±7.22%. Surgery led to an improvement in the GLS; the mean difference was 3.23% [95% CI=1.96 to 4.49%] during a median follow up time of 5 (interquartile range 4-6) months. The preoperative GLS correlated with the postoperative LV mass index (LVMI) r=0.526, P=0.001 and the intraventricular septal thickness in diastole (IVSd) r=0.462, P=0.003. Furthermore, patients with a normal GLS (≤-18.9%) at baseline experienced a better recovery of their LV morphology and systolic function during the postoperative course compared to those with an abnormal GLS (>-18.9%). The effect size, hedges g, was at least >0.75 for the LVMI, IVSd, intraventricular septal thickness in systole (IVSs), left ventricular posterior wall thickness in diastole (LVPWd) and LVEF, suggesting a clinically significant difference between subgroups at follow-up. CONCLUSION: A normal preoperative left ventricular global longitudinal strain is associated with an improved left ventricular reverse remodeling and systolic function following surgery to resolve aortic stenosis.