Atrial fibrosis and decreased connexin 43 in rat hearts after exposure to high-intensity infrasound.

BACKGROUND: Noise is an important environmental risk factor. Industrial environments are rich in high-intensity infrasound (hi-IFS), which we have found to induce myocardial and coronary perivascular fibrosis in rats. The effects of exposure to IFS on the ventricles have been studied, but not on the atria. We hypothesized that rats exposed to hi-IFS develop atrial remodeling involving fibrosis and connexin 43, which we sought to evaluate. MATERIAL AND METHODS: Seventy-two Wistar rats, half exposed to hi-IFS (120 dB, <20 Hz) during a maximum period of 12 weeks and half age-matched controls, were studied. Atrial fibrosis was analyzed by Chromotrope-aniline blue staining. The immunohistochemical evaluation of Cx43 was performed using the polyclonal antibody connexin-43 m diluted 1:1000 at 4 °C overnight. Digitized images were obtained with an optical microscope using 400× magnifications. The measurements were performed using image J software. A two-way ANOVA model was used to compare the groups. RESULTS: The mean values of the ratio "atrial fibrosis / cardiomyocytes" increased to a maximum of 0.1095 ± 0,04 and 0.5408 ± 0,01, and of the ratio "CX43 / cardiomyocytes" decreased to 0.0834 ± 0,03 and 0.0966 ± 0,03, respectively in IFS-exposed rats and controls. IFS-exposed rats exhibited a significantly higher ratio of fibrosis (p < .001) and lower ratio of Cx43 (p = .009). CONCLUSION: High-intensity infrasound exposure leads to an increase in atrial interstitial fibrosis and a decrease in connexin 43 in rat hearts. This finding reinforces the need for further experimental and clinical studies concerning the effects of exposure to infrasound.

Histomorphometric evaluation of the small coronary arteries in rats exposed to industrial noise.

UNLABELLED: Morphological changes induced by industrial noise (IN) have been experimentally observed in several organs. Histological observations of the coronary arteries showed prominent perivascular tissue and fibrosis among IN-exposed rats. The effects on the small arteries are unknown. OBJECTIVE: To evaluate the histomorphometric changes induced by IN on rat heart small arteries. METHODS: Twenty Wistar rats exposed to IN during a maximum period of seven months and 20 age-matched controls were studied. Hearts were transversely sectioned from ventricular apex to atria and a mid-ventricular fragment was selected for analysis. The histological images were obtained with an optical microscope using 400× magnifications. A total of 634 arterial vessels (298 IN-exposed and 336 controls) were selected. The mean lumen-to-vessel wall (L/W) and mean vessel wall-to-perivascular tissue (W/P) ratios were calculated using image J software. RESULTS: There were no differences between exposed and control animals in their L/W ratios (p=0.687) and time variations in this ratio were non-significant (p=0.110). In contrast, exposed animals showed lower W/P ratios than control animals (p<0.001), with significant time variations (p=0.004). CONCLUSIONS: Industrial noise induced an increase in the perivascular tissue of rat small coronary arteries, with significant development of periarterial fibrosis.

Very-early detection of atrial fibrillation after ablation evaluated by a wearable ECG-patch predicts late blanking period recurrence: Preliminary data from a prospective registry.

Introduction: Atrial fibrillation (AF) ablation represents a safe and effective procedure to restore sinus rhythm. The idea that post-procedural AF episodes - during the blanking period - are not considered treatment failure has been increasingly challenged. The E-Patch, a single-use adhesive electrode, facilitates extended continuous ECG monitoring for 120 h. This pilot study aims to assess the effectiveness of this ambulatory monitoring device and investigate whether very-early AF recurrence correlates with delayed blanking period ablation outcomes. Methods: We conducted a single-center, prospective, longitudinal study, including consecutive post-ablation patients monitored with the E-patch. The ability of the device to continuously record was analyzed, as well as the occurrence of AF episodes during external 7-day loop-recorder in the 2nd-month post-ablation. Results: We included 40 patients, median age 62 years (IQR 56-70). E-Patch monitoring was obtained for a median of 118 h (IQR 112-120), with no discomfort nor interpretation artefacts. Very-early AF recurrence was detected in 11 (27.5 %) patients, with a median AF burden of 7 % (IQR 6 %-33 %). Late-blanking period AF was detected in 13 (33 %) of the external 7-day loop recordings. Of the 11 patients that had very-early AF recurrence, 10 (91 %) had late-blanking AF. Very-early AF detection showed 77 % (95 % CI 64 %-90 %) sensitivity and 96 % (95 % CI 90-100 %) specificity in predicting late-blanking AF, with a non-parametric ROC curve AUC of 0.903 (95 % 0.797--1.0). Conclusion: The E-Patch was able to detect very-early AF during an extended period. Very-early AF detection emerges as a predictor of AF recurrence during the late blanking period post-ablation.

Epicardial adipose tissue volume assessed by cardiac CT as a predictor of atrial fibrillation recurrence following catheter ablation.

INTRODUCTION: In patients with atrial fibrillation (AF), up to one third have recurrence after a first catheter ablation (CA). Epicardial adipose tissue (EAT) has been considered to be closely related to AF, with a potential role in its recurrence. We aimed to evaluate the association between the volume of EAT measured by cardiac computed tomography (CT) and AF recurrence after CA. METHODS: Consecutive AF patients underwent a standardized cardiac CT protocol for quantification of EAT, thoracic adipose volume (TAV) and left atrium (LA) volume before CA. An appropriate cut-off of EAT was determined and risk recurrence was estimated. RESULTS: 305 patients (63.6 % male, mean age 57.5 years, 28.2 % persistent AF) were followed for 24 months; 23 % had AF recurrence at 2-year mark, which was associated with higher EAT (p = 0.037) and LAV (p < 0.001). Persistent AF was associated with higher EAT volumes (p = 0.010), TAV (p = 0.003) and LA volumes (p < 0.001). EAT was predictive of AF recurrence (p = 0.044). After determining a cut-off of 92 cm3, survival analysis revealed that EAT volumes > 92 cm3 showed higher recurrence rates at earlier time points after the index ablation procedure (p = 0.006), with a HR of 1.95 (p = 0.008) of AF recurrence at 2-year. After multivariate adjustment, EAT > 92 cm3 remained predictive of AF recurrence (p = 0.028). CONCLUSION: The volume of EAT measured by cardiac CT can predict recurrence of AF after ablation, with a volume above 92 cm3 yielding almost twice the risk of arrhythmia recurrence in the first two years following CA. Higher EAT and TAV are also associated with persistent AF.

Apical or Septal Right Ventricular Location in Patients Receiving Defibrillation Leads: A Systematic Review and Meta-Analysis.

This study reviews the published data comparing the efficacy and safety of apical and septal right ventricle defibrillator lead positioning at 1-year follow-up. Systemic research on Medline (PubMed), ClinicalTrials.gov, and Embase was performed using the keywords "septal defibrillation," "apical defibrillation," "site defibrillation," and "defibrillation lead placement," including implantable cardioverter-defibrillator and cardiac resynchronization therapy devices. Comparisons between apical and septal position were performed regarding R-wave amplitude, pacing threshold at a pulse width of 0.5 ms, pacing and shock lead impedance, suboptimal lead performance, left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter, readmissions due to heart failure and mortality rates. A total of 5 studies comprising 1438 patients were included in the analysis. Mean age was 64.5 years, 76.9% were male, with a median LVEF of 27.8%, ischemic etiology in 51.1%, and a mean follow-up period of 26.5 months. The apical lead placement was performed in 743 patients and septal lead placement in 690 patients. Comparing the 2 placement sites, no significant differences were found regarding R-wave amplitude, lead impedance, suboptimal lead performance, LVEF, left ventricular end-diastolic diameter, and mortality rate at 1-year follow-up. Pacing threshold values favored septal defibrillator lead placement (P = 0.003), as well as shock impedance (P = 0.009) and readmissions due to heart failure (P = 0.02). Among patients receiving a defibrillator lead, only pacing threshold, shock lead impedance, and readmission due to heart failure showed results favoring septal lead placement. Therefore, generally, the right ventricle lead placement does not appear to be of major importance.

Dilated Cardiomyopathy: A Comprehensive Approach to Diagnosis and Risk Stratification.

Dilated cardiomyopathy (DCM) represents one of the most common causes of non-ischemic heart failure, characterised by ventricular dilation alongside systolic dysfunction. Despite advances in therapy, DCM mortality rates remain high, and it is one of the leading causes of heart transplantation. It was recently recognised that many patients present minor structural cardiac abnormalities and express different arrhythmogenic phenotypes before overt heart-failure symptoms. This has raised several diagnostic and management challenges, including the differential diagnosis with other phenotypically similar conditions, the identification of patients at increased risk of malignant arrhythmias, and of those who will have a worse response to medical therapy. Recent developments in complementary diagnostic procedures, namely cardiac magnetic resonance and genetic testing, have shed new light on DCM understanding and management. The present review proposes a comprehensive and systematic approach to evaluating DCM, focusing on an improved diagnostic pathway and a structured stratification of arrhythmic risk that incorporates novel imaging modalities and genetic test results, which are critical for guiding clinical decision-making and improving outcomes.

A simplified single transseptal puncture approach using high-density 3D voltage mapping for atrial fibrillation ablation: acute complications and long-term results.

Background: An ablation catheter and a circular mapping catheter requiring a double transeptal puncture (TSP) for left atrial access have been conventionally used for atrial fibrillation (AF) ablation. Recently, different operators have combined a single transseptal puncture technique with 3D high-density mapping catheters for pulmonary vein isolation (PVI). Objective: This study aims to compare two strategies, single vs. double TSP, regarding the duration of the procedure, radiation time, complication rates, and outcomes. Methods: Retrospective analysis of a large cohort of consecutive patients that underwent first PVI with radiofrequency energy (RF), using a point-by-point strategy, with a 3D mapping system, either with single or double TSP, according to the operator's choice. Results: 285 patients with a mean age of 59.5 ± 11.6 years (36.5% female, 67.7% paroxysmal AF) underwent a point-by-point catheter ablation with RF between July 2015 and March 2020. The mean CHA2DS2-VASc score was 1.7 ± 1.3. Single TSP was performed in 115 (40.3%) patients and double TSP in 170 (59.6%). The operator's experience (≥5 years of AF ablation procedures) was equally distributed among the two groups. The average procedure time (133 ± 31.7 min vs. 123 ± 35.5 min, for single and double TSP, respectively) did reach a statistical difference between both groups (p = 0.008), but there was a substantial advantage regarding fluoroscopy time (13 ± 6.3 min vs. 19 ± 9.1 min, for single and double TSP, respectively; p < 0.001). Acute major complications present similar rates in both groups (2.6% vs. 2.3%, p = 0.799). At the 2-year follow-up, both groups had a similar sinus rhythm maintenance rate (76.5% vs. 78.8%, p = 0.646). Conclusion: A simplified single-TSP technique using high-density multi-electrode 3D mapping is a safe and highly successful option for AF ablation. This approach yields a substantial reduction in fluoroscopy time, with the potential to avoid acute complications, compared to a conventional double-TSP strategy.

Validation of a Heart Failure Risk Score in a Cohort of Cardiac Resynchronization Therapy Patients Under Remote Monitoring: Results from the TriageHF™ Algorithm.

The heart failure risk status (HFRS) is a validated dynamic tool for risk score prediction, based on the TriageHF™ algorithm (Medtronic, Minneapolis, MN, USA), for the occurrence of a heart failure (HF) event in the 30 days following a remote monitoring (RM) transmission. The aim of this study was to evaluate the accuracy of the HFRS in predicting an unplanned hospital admission due to HF decompensation in a real-world cohort of patients submitted to cardiac resynchronization therapy (CRT). We conducted a single-center review of a cohort of 40 consecutive HF patients, under RM, with CRT devices using the HFRS of the TriageHF™ algorithm. The correlation of the HFRS with hospital admissions was analyzed. During a mean follow-up of 36 months, a stepwise increase in the HFRS was significantly associated with a higher risk of HF admission (odds ratio, 12.7; 95% confidence interval, 3.2-51.5; P < .001), and the HFRS was demonstrated to have good discrimination for HF hospitalization, with an area under the receiver-operating characteristic curve of 0.812. The TriageHF™ algorithm effectively predicted HF-related hospitalization in a cohort of CRT patients during long-term RM follow-up, providing a novel clinical pathway to optimize the clinical management of this complex population.

Long-term outcomes of non-contact multi-electrode balloon catheter mapping-guided ablation of ventricular arrhythmias originating from the outflow tract.

INTRODUCTION: The outflow tract (OT) regions of the ventricles are a common location of origin for idiopathic ventricular arrhythmias (VA). Non-contact mapping (NCM) with a multi-electrode balloon catheter Ensite-Array enables three-dimensional reconstruction of the geometry of the cardiac chambers and accurate mapping of the propagation map, based on a single beat analysis, facilitating the ablation and contributing procedure success. OBJECTIVE: Assessment of the feasibility and long-term outcomes following NCM-guided OT VA ablation. METHODS: Single center retrospective analysis of patients admitted for symptomatic OT VA ablation. Demographic and clinical characteristics of patients, procedure data and long-term outcomes were assessed. RESULTS: Fifty-eight patients (79.3% female, age 43.9±17.6 years) were considered, 89.7% without structural heart disease. In 85.7% of the cases left ventricle ejection fraction (LVEF) was preserved (LVEF≥50%), 8.6% had mild systolic dysfunction (LVEF 40%-49%) and 5.7% had moderate systolic dysfunction (LVEF 30%-39%). Twenty-four-hour Holter recording documented sustained VA episodes in 12.1% of the patients, non-sustained VA in 31.0%, and >10 000 premature ventricular complex (PVC)/24 h in 56.9%, with an ECG suggesting right ventricular OT origin in 84.5%. There was total elimination of PVC in 87.9% cases and a significant reduction in 3.4%. During a mean follow-up of 5.5 years, 87.9% patients remained asymptomatic without medication, 12.1% underwent re-ablation due to symptomatic PVC recurrence, and two cases underwent a third successful intervention. CONCLUSION: Non-contact mapping-guided multi-electrode balloon catheter VA ablation is a highly effective and safe procedure, with a low rate of long-term recurrence.

The atrial fibrillation burden during the blanking period is predictive of time to recurrence after catheter ablation.

Objective: This study aimed to assess whether atrial fibrillation (AF) occurrence or its corresponding daily mean burden (in minutes/day) during the mid to late blanking period after pulmonary vein isolation (PVI), predicts AF recurrence. Methods: Analysis of consecutive first PVI ablation patients undergoing prolonged electrocardiogram (ECG) monitoring during the second and third months after PVI. The clinical variables, total AF burden, and their relationship with time to recurrence were studied. Results: 477 patients with a mean age of 56.9 (SD = 12.3) years (63.7 % male; 71.7 % paroxysmal AF), from which 317 (66.5 %) had an external event recorder between 30 and 90 days after ablation. Median follow-up of 16.0 (P 25:12.0: P 75:33.0) months, 177 (37 %) patients had an AF recurrence, with 106 (22.2 %) having the first episode after 12 months of follow-up. In the group of patients with an event recorder, 80 (25.2 %) had AF documented during the blanking period. Multivariable analysis showed that AF during the blanking period was associated with a 4-fold higher risk of recurrence (HR: 3.98; 95 %CI: 2.95-5.37), and, compared to patients in sinus rhythm, those with an AF burden ≥ 23 min/day had an approximately 7-fold higher risk of recurrence (HR estimate: 6.79; 95 %CI: 4.56-10.10). Conclusions: The probability of experiencing AF recurrence can be predicted by atrial tachyarrhythmia episodes during the second and third months after PVI. Atrial arrhythmias burden > 23 min/day has a high predictive ability for recurrence.

Very late coronary stent thrombosis after discontinuation of antiplatelet therapy.

Percutaneous transluminal coronary angioplasty (PTCA) with stent placement is widely used to achieve myocardial revascularization in patients with symptomatic ischemic heart disease and significant coronary artery stenosis. Drug-eluting stents are used in most patients undergoing percutaneous angioplasty. Stent thrombosis is an uncommon but serious complication, manifested mostly by sudden death or acute ST-elevation myocardial infarction. The authors report the case of a 68-year-old patient with acute anterior ST-elevation myocardial infarction. Five years previously, she had had a similar presentation and underwent primary angioplasty of the left anterior descending artery with implantation of a drug-eluting stent. The patient was discharged under antithrombotic therapy. She discontinued antiplatelet therapy and two days later suffered an acute anterior myocardial infarction. Primary angioplasty revealed stent thrombosis.

[Impact of age on treatment and outcomes after acute myocardial infarction, particularly in very elderly patients]. / Impacto da idade no tratamento e resultados após enfarte agudo do miocárdio em particular nos muito idosos.

INTRODUCTION: The elderly population admitted for acute myocardial infarction is increasing. This group is not well studied in international trials and is probably treated with a more conservative approach. OBJECTIVES: To evaluate the presentation and treatment of myocardial infarction according to age, particularly in very elderly patients. METHODS: We studied 1242 consecutive patients admitted with acute myocardial infarction, assessing in-hospital, 30-day and one-year mortality during follow-up for each age-group. Patients were divided into four groups according to age: <45 years (7.6%); 45-64 years (43.3%); 65-74 years (23.4%); and ≥75 years (25.7%). RESULTS: Elderly patients had a worse risk profile (except for smoking), more previous history of coronary disease and a worse profile on admission, with the exception of lipid profile, which was more favorable. With regard to treatment of the elderly, although less optimized than in other age-groups, it was significantly better compared to other registries, including for percutaneous coronary angioplasty. Both complications and mortality were worse in the older groups. In elderly patients (≥75 years), adjusted risk of mortality was 4.9-6.3 times higher (p<0.001) than patients in the reference age-group (45-64 years). In these patients, the independent predictors of death were left ventricular function and renal function, use of beta-blockers being a predictor of survival. CONCLUSIONS: Elderly patients represent a substantial proportion of the population admitted with myocardial infarction, and receive less evidenced-based therapy. Age is an independent predictor of short- and medium-term mortality.

Benefits of cardiac resynchronization therapy in "very dilated cardiomyopathy".

INTRODUCTION: Recent clinical trials have studied parameters that could predict response to cardiac resynchronization therapy (CRT) in patients with advanced heart failure. Left ventricular end-diastolic dimension (LVEDD) is regarded as a possible predictor of response to CRT. OBJECTIVE: To study the response to CRT in patients with very dilated cardiomyopathy, i.e. those at a more advanced stage of the pathology, analyzing both the responder rate and reverse remodeling in two groups of patients classified according to LVEDD. METHODS: We performed a retrospective analysis of 71 patients who underwent CRT (aged 62 +/- 11 years; 65% male; 93% in NYHA functional class > or = III; 31% with ischemic cardiomyopathy; left ventricular ejection fraction [LVEF] 25.6 +/- 6.8%; 32% in atrial fibrillation; QRS 176 +/- 31 ms). Twenty-two (31%) patients with LVEDD > or = 45 mm/m2 (49.2 +/- 3.5 mm/m2) were considered to have very dilated cardiomyopathy (Group A) and 49 patients had LVEDD > 37 mm/m2 and < 45 mm/m2 (39.4 +/- 3.8 mm/m2) (Group B). All patients were assessed by two-dimensional echocardiography at baseline and six months after CRT. The following parameters were analyzed: NYHA functional class, LVEF and LVEDD. Responders were defined clinically (improvement of > or = 1 NYHA class) and by echocardiography, with a minimum 15% increase over baseline LVEF combined with a reduction in LVEDD (reverse remodeling). RESULTS: There were no significant differences in baseline demographic characteristics between the two groups. At six-month followup, we observed an improvement in LVEF (delta 8.5 +/- 11.8%) and a reduction in LVEDD (delta 3.7 +/- 6.8 mm/m2), with fifty-seven (79%) patients being classified as clinical responders. The percentage of patients with reverse remodeling was similar in both groups (64% vs. 73%, p = NS), as were percentages of improved LVEF (delta 6.3 +/- 11% vs. delta 9.6 +/- 12%; p = NS) and decreased LVEDD (delta 3.7 +/- 5.5 mm/m2 vs. delta 3.7 +/- 7.4 mm/m2; p = NS). We found a higher percentage of clinical responders in patients with very dilated cardiomyopathy (96% vs. 72%, p < 0.05). CONCLUSION: In this study, a significant number of responders showed reverse remodeling after CRT. Although a higher percentage of patients with very dilated cardiomyopathy showed improvement in functional class, the extent of reverse remodeling was similar in both groups.

Stent fracture: case report and literature review.

We report the case of a man presenting with acute myocardial infarction and a history of percutaneous coronary intervention with implantation of a drug-eluting stent, which was now fractured. This case highlights the growing recognition of stent fracture as a potential mechanism for late stent thrombosis in the drug-eluting stent era. Following the case report, we review the literature on the incidence, contributing factors and clinical impact of stent fracture.

Impact of substrate-based ablation for ventricular tachycardia in patients with frequent appropriate implantable cardioverter-defibrillator therapy and dilated cardiomyopathy: Long-term experience with high-density mapping.

INTRODUCTION: Recurrent ventricular tachycardia (VT) episodes have a negative impact on the clinical outcome of implantable cardioverter-defibrillator (ICD) patients. Modification of the arrhythmogenic substrate has been used as a promising approach for treating recurrent VTs. However, there are limited data on long-term follow-up. AIM: To analyze long-term results of VT substrate-based ablation using high-density mapping in patients with severe left ventricular (LV) dysfunction and recurrent appropriate ICD therapy. METHODS: We analyzed 20 patients (15 men, 55% with non-ischemic cardiomyopathy, age 58±15 years, LV ejection fraction 32±5%) and repeated appropriate shocks or arrhythmic storm (>2 shocks/24 h) despite antiarrhythmic drug therapy and optimal heart failure medication. All patients underwent ventricular programmed stimulation (600 ms/S3) to document VT. A sinus rhythm (SR) voltage map was created with a three-dimensional electroanatomic mapping system (CARTO, Biosense Webster, CA) using a PentaRay® high-density mapping catheter (Biosense Webster, CA) to delineate areas of scarred myocardium (ventricular bipolar voltage ≤0.5 mV - dense scar; 0.5-1.5 mV - border zone; ≥1.5 mV - healthy tissue) and to provide high-resolution electrophysiological mapping. Substrate modification included elimination of local abnormal ventricular activities (LAVAs) during SR (fractionated, split, low-amplitude/long-lasting, late potentials, pre-systolic), and linear ablation to obtain scar homogenization and dechanneling. Pace-mapping techniques were used when capture was possible. The LV approach was retrograde in nine cases, transseptal in five and epi-endocardial in four. In two patients ablation was performed inside the right ventricle. RESULTS: LAVAs and scar areas were modified in all patients. Mean procedure duration was 149 min (105-220 min), with radiofrequency ranging from 18 to 70 min (mean 33 min) and mean fluoroscopy time of 15 min. Non-inducibility was achieved in 75% of cases (in four patients with hemodynamic deterioration and an LV assist device, VT inducibility was not performed). There were two cases of pericardial tamponade, drained successfully. During a follow-up of 50±24 months, 65% had no VT recurrences. Among the seven patients with recurrences, three underwent redo ablation and four, with fewer VT episodes, received appropriate ICD therapy. There were five hospital readmissions due to heart failure decompensation, one patient died in the first week after unsuccessful ablation of a VT storm and three died (stroke and pneumonia) >1 year after ablation. CONCLUSION: Catheter ablation based on substrate modification is feasible and safe in patients with frequent VTs and severe LV dysfunction. This approach may be of clinical relevance, with potential long-term benefits in reducing VT burden.

Noncompaction cardiomyopathy--a review of eight cases.

Left ventricular noncompaction is a genetic disorder that is thought to be related to an arrest in endomyocardial development. It is characterized by the presence of a prominent trabecular meshwork and deep recesses. In order to better characterize this recently described disorder, whose prognosis remains unclear, we review eight cases diagnosed at our hospital, describing their clinical, electrocardiographic and echocardiographic features as well as therapy and follow-up. We also discuss the most relevant data from the literature concerning pathogenesis, clinical presentation, diagnostic criteria, therapy and prognosis.

Usefulness of tissue Doppler imaging to predict arrhythmic events in adults with repaired tetralogy of Fallot.

INTRODUCTION: Adults with repaired tetralogy of Fallot (TOF) may be at risk for progressive right ventricular (RV) dilatation and dysfunction, which is commonly associated with arrhythmic events. In frequently volume-overloaded patients with congenital heart disease, tissue Doppler imaging (TDI) is particularly useful for assessing RV function. However, it is not known whether RV TDI can predict outcome in this population. OBJECTIVE: To evaluate whether RV TDI parameters are associated with supraventricular arrhythmic events in adults with repaired TOF. METHODS: We studied 40 consecutive patients with repaired TOF (mean age 35 +/- 11 years, 62% male) referred for routine echocardiographic exam between 2007 and 2008. The following echocardiographic measurements were obtained: left ventricular (LV) ejection fraction, LV end-systolic volume, LV end-diastolic volume, RV fractional area change, RV end-systolic area, RV end-diastolic area, left and right atrial volumes, mitral E and A velocities, RV myocardial performance index (Tei index), tricuspid annular plane systolic excursion (TAPSE), myocardial isovolumic acceleration (IVA), pulmonary regurgitation color flow area, TDI basal lateral, septal and RV lateral peak diastolic and systolic annular velocities (E' 1, A' 1, S' 1, E' s, A' s, S' s, E' rv, A' rv, S' rv), strain, strain rate and tissue tracking of the same segments. QRS duration on resting ECG, total duration of Bruce treadmill exercise stress test and presence of exercise-induced arrhythmias were also analyzed. The patients were subsequently divided into two groups: Group 1--12 patients with previous documented supraventricular arrhythmias (atrial tachycardia, fibrillation or flutter) and Group 2 (control group)--28 patients with no previous arrhythmic events. Univariate and multivariate analysis was used to assess the statistical association between the studied parameters and arrhythmic events. RESULTS: Patients with previous events were older (41 +/- 14 vs. 31 +/- 6 years, p = 0.005), had wider QRS (173 +/- 20 vs. 140 +/- 32 ms, p = 0.01) and lower maximum heart rate on treadmill stress testing (69 +/- 35 vs. 92 +/- 9%, p = 0.03). All patients were in NYHA class I or II. Clinical characteristics including age at corrective surgery, previous palliative surgery and residual defects did not differ significantly between the two groups. Left and right cardiac chamber dimensions and ventricular and valvular function as evaluated by conventional Doppler parameters were also not significantly different. Right ventricular strain and strain rate were similar between the groups. However, right ventricular myocardial TDI systolic (Sa: 5.4+2 vs. 8.5 +/- 3, p = 0.004) and diastolic indices and velocities (Ea, Aa, septal E/Ea, and RV free wall tissue tracking) were significantly reduced in patients with arrhythmias compared to the control group. Multivariate linear regression analysis identified RV early diastolic velocity as the sole variable independently associated with arrhythmic history (RV Ea: 4.5 +/- 1 vs. 6.7 +/- 2 cm/s, p = 0.01). A cut-off for RV Ea of < 6.1 cm/s identified patients in the arrhythmic group with 86% sensitivity and 59% specificity (AUC = 0.8). CONCLUSIONS: Our results suggest that TDI may detect RV dysfunction in patients with apparently normal function as assessed by conventional echocardiographic parameters. Reduction in RV early diastolic velocity appears to be an early abnormality and is associated with occurrence of arrhythmic events. TDI may be useful in risk stratification of patients with repaired tetralogy of Fallot.

Results of primary angioplasty in a reference center: in-hospital outcomes.

INTRODUCTION: Primary angioplasty is accepted as the preferred treatment for acute myocardial infarction in the first 12 hours. However, outcomes depend to a large extent on the volume of activity and experience of the center. Continuous monitoring of methods and results obtained is therefore crucial to quality control. OBJECTIVE: To describe the demographic, clinical and angiographic characteristics as well as in-hospital outcomes of patients undergoing primary PCI in a high-volume Portuguese center. We also aimed to identify variables associated with in-hospital mortality in this population. METHODS: This was a retrospective registry of consecutive primary PCIs performed at Santa Marta Hospital between January 2001 and August 2007. Demographic, clinical, and angiographic characteristics and in-hospital outcomes were analyzed. Independent predictors of in-hospital mortality were identified by multivariate logistic regression analysis. RESULTS: A total of 1157 patients were identified, mean age 61+/-12 years, 76% male. Mean pain-to-balloon time was 7.6 hours and primary angiographic success was 88%. Overall in-hospital mortality was 6.9%, or 5.5% if patients presenting in cardiogenic shock were excluded from the analysis. Previous history of heart failure, cardiogenic shock on admission, invasive ventilatory support, major hemorrhage, and age over 75 years were found to be associated with increased risk of in-hospital death. CONCLUSIONS: In this center primary PCI is effective and safe. Angiographic success rates and in-hospital mortality and morbidity are similar to other international registries. Patients at increased risk for adverse outcome can be identified by simple clinical characteristics such as advanced age, cardiogenic shock on admission, mechanical ventilation and major hemorrhage during hospitalization.

An inappropriate shock after reprogramming tachycardia zones.

A patient with an implantable cardioverter-defibrillator (ICD) (Abbott®) had episodes of slow monomorphic ventricular tachycardia (VT) and his ICD was programmed with three tachycardia zones. During the follow-up, he received an inappropriate shock. Upon interrogation (of the device), trigeminal pattern binned as ventricular sensing (VS)-VS-ventricular fibrillation (VF) was detected. VF was assumed according to binning system. When VF is present, discrimination algorithms are not available and five consecutive sinus beats are necessary to reset binning system. Catheter ablation was performed to treat VT in order to reprogram tachycardia zones.