Early Atherosclerosis and Conduction Defect in a Rare Case of Dunnigan Type Familial Partial Lipodystrophy.

A 45-year-old female patient was admitted to the emergency department with syncope. Her medical history revealed a diagnosis of Familial Partial Lipodystrophy 2 (FPLD2). The patient's electrocardiogram showed a complete atrioventricular (A-V) block, and she had a history of insulin-dependent diabetes mellitus and coronary artery bypass surgery. A severe stenosis was observed in the aortic right coronary artery saphenous vein graft during coronary angiography, which was successfully revascularized. Subsequently, due to persistant syncope attacks, a permanent pacemaker was implanted after an electrophysiological study. This case highlights that serious cardiac conduction defects in patients with FPLD2 may not only be related to coronary artery disease but can also present as direct conduction defects.

Angiotensin receptor neprilysin inhibitor for patients with heart failure and reduced ejection fraction: Real-world experience from Turkey (ARNi-TR).

OBJECTIVE: Heart failure (HF) is a growing public health problem with high morbidity and mortality. Recently, angiotensin receptor neprilysin inhibitor (ARNi) has emerged as a promising treatment for HF with reduced ejection fraction (HFrEF). Here, we shared our experience with the use of ARNi in HFrEF from multiple centers in Turkey. METHODS: The ARNi-TR is a multicenter, noninterventional, retrospective, observational study. Overall, 779 patients with HF from 22 centers in Turkey who were prescribed sacubitril/valsartan were examined. Initial clinical status, biochemical and echocardiographic parameters, and New York Heart Association functional class (NYHA-FC) values were compared with follow-up values after 1 year of ARNi use. In addition, the effect of ARNi on number of annual hospitalizations was investigated, and the patients were divided into 2 groups, depending on whether ARNi was initiated at hospitalization or under outpatient clinic control. RESULTS: N-terminal pro-brain natriuretic peptide (NT-proBNP), left-ventricle ejection fraction (LV-EF), and NYHA-FC values improved significantly in both groups (all parameters, p<0.001) within 1-year follow-up. In both groups, a decrease in hemoglobin A1c (HbA1c) values was observed in ARNi use (p<0.001), and a decrease in daily diuretic doses and hospitalizations owing to HF were observed after ARNi use (all comparisons, p<0.001). Hypotension (16.9%) was the most common side effect in patients using ARN. CONCLUSION: The ARNi-TR study offers comprehensive real-life data for patients using ARNi in Turkey. The use of ARNi has shown significant improvements in FC, NT-proBNP, HbA1c levels, and LV-EF. Likewise, reductions in the number of annual hospitalizations and daily furosemide doses for HF were seen in this study.

Is the presence of left atrial diverticulum associated with recurrence in patients undergoing catheter ablation for atrial fibrillation?

INTRODUCTION: Catheter ablation (CA) for atrial fibrillation (AF) has been a major cornerstone in the management of AF. Despite promising advances in CA techniques, long-term results reveal a high rate of recurrence after the procedure. Left atrial diverticulum (LAD), a common anatomic variant of the left atrium, was previously shown to be associated with increased risk of thrombus formation, cardiac perforation and arrhythmia. In this study we aimed to investigate the relationship between LAD and recurrence in patients undergoing CA for AF. MATERIAL AND METHODS: A total of 100 consecutive patients with a mean age of 53 ±12.1 years (53% male) underwent radiofrequency (RF) (46, 46%) or cryoballoon (54, 54%) catheter ablation for atrial fibrillation preceded by cardiac computed tomography (CT) imaging. Clinical and procedural characteristics of the patients with and without AF recurrence were compared. RESULTS: Twenty-three (23%) patients had AF recurrence and 77 (77%) patients had no recurrence. The clinical parameters such as hypertension, diabetes mellitus, coronary artery disease and stroke did not differ between the groups. Left atrium diameter was significantly different between the two groups (4.1 ±0.5 vs. 3.9 ±0.5, p = 0.042). Presence of LAD was not different between the two groups (7 (31.8) vs. 21 (28.8); p = 0.794). Multivariate logistic regression analysis revealed RF ablation as the most important independent variable for AF recurrence (ß = 3.115, p< 0.001, OR = 22.526, 95% CI: 4.287-118.351). CONCLUSIONS: The presence of left atrial diverticulum is not associated with recurrence in patients undergoing RF and cryoballoon CA for atrial fibrillation.

Effect of cardiac resynchronization therapy on mitral valve geometry: a novel aspect as "reversed mitral remodeling".

Amelioration of the valvular geometry is a possible mechanism for mitral regurgitation (MR) improvement in patients receiving cardiac resynchronization therapy (CRT). We aimed to establish the precise definition, incidence, and predictors of reversed mitral remodeling (RMR), as well as the association with MR improvement and short-term CRT outcome. Ninety-five CRT recipients were retrospectively evaluated for the end-point of "MR response" defined as the absolute reduction in regurgitant volume (RegV) at 6 months. To identify RMR, changes in mitral deformation indices were tested for correlation with MR response and further analyzed for functional and echocardiographic CRT outcomes. Overall, MR response was observed in 50 patients (53%). Among the echocardiographic indices, the change in tenting area (TA) had the highest correlation with the change in RegV (r = 0.653, p < 0.001). The mean TA significantly decreased in MR responders (4.15 ± 1.05 to 3.67 ± 1.01 cm2 at 6 months, p < 0.001) and increased in non-responders (3.68 ± 1.04 to 3.98 ± 0.97 cm2, p = 0.014). The absolute TA reduction was used to identify patients with RMR (47%) which was found to be associated with higher rates of functional improvement (p = 0.03) and volumetric CRT response (p = 0.036) compared to those without RMR. Non-ischemic etiology and the presence of LBBB independently predicted RMR at multivariate analysis. In conclusion, reduction in TA is a reliable index of RMR, which relates to MR response, and functional and echocardiographic improvement with CRT. LBBB and non-ischemic etiology are independent predictors of RMR.

The effects of supraphysiological oestrogen levels on ventricular repolarisation parameters.

BACKGROUND: The frequency of arrhythmic death developing without a structural cardiac disease is higher in women. Also, female sex is an independent risk factor regarding development of torsades de pointes. Several studies have been conducted on the physiological and therapeutic effects of sex hormones on the cardiac conduction system. AIM: In this study we aim to examine the effect of hormonal changes, especially supraphysiological E2 level changes occurring during in vitro fertilisation treatment, on ventricular repolarisation parameters. METHODS: The study included female patients aged between 23 and 39 years, who were administered controlled ovarian hyperstimulation treatment. Patients' electrocardiograms and blood samples were obtained and analysed before and after the ovarian hyperstimulation treatment. RESULTS: Mean QTc intervals before ovarian hyperstimulation were 411.9 ± 23.7 ms. Measurements during oestradiol peak were calculated as 420.7 ± 23.3 ms, and the QTc interval increase was significant (p = 0.007). Corrected QT dispersion averages were not significant before or after hyperstimulation (53 ± 17 ms vs. 54.5 ± 18.2 ms, respectively, p > 0.05). Tp-e, J-T peak, and PR dispersion changes were not significant after the ovarian hyperstimulation therapy. CONCLUSIONS: Supraphysiological oestradiol levels that occur during controlled ovarian hyperstimulation cause prolongation of QTc intervals, but not to a pathological level. Although this prolongation is not significant in healthy individuals, it might increase ventricular arrhythmia risk in patients with congenital long QT syndrome and in patients taking medication that prolongs QT.

The relationship between the S-wave in lead 1 and recurrence of RVOT PVC ablation.

BACKGROUND: Radiofrequency catheter ablation (CA) is a common non-pharmacological treatment option for ventricular premature contractions (PVCs) originating from right ventricular outflow tract (RVOT). In this study, we aimed to investigate the relationship between recurrence after CA for RVOT-PVC and S-wave in lead 1 that was shown to be associated with RVOT depolarization. METHODOLOGY: A total of 104 patients who were referred to our clinic for CA for idiopathic RVOT-PVC between 2012 and 2015years were enrolled. All ECG parameters were measured before and after the ablation procedure. RESULTS: Ablation was successful in 100 patients (96,1%). These patients with successful ablation were followed for a mean duration of 1078days. 13 patients (13%) had recurrence. Univariate logistic regression analysis revealed age (odds ratio: 1.916, p:0,012), presence of post-procedural S1 (odds ratio:1.040 p:0,028), post-procedural S1 area (oddsratio:1.023 p:0,041), ΔS1 area (odds ratio:1.242 p:0,004) as predictors for recurrence. Multivariate logistic regression analysis detected age (odds ratio:1.053 p:0,032) and ΔS1 area (odds ratio:0.701 p:0,009) as predictors for recurrence. CONCLUSION: Radiofrequency CA for RVOT-PVC can be performed with high procedural success and low complication rates. Age and ΔS1 area might be helpful for prediction of recurrence after CA.

Pocket haematoma after cardiac electronic device implantation in patients receiving antiplatelet and anticoagulant treatment: a single-centre experience.

Objective In modern cardiology practice, implantation of cardiac electronic devices in patients taking anticoagulant or antiplatelet therapy is a common clinical scenario. Bleeding complications are of particular concern in this patient population and pocket haematoma is one of the most frequent complications. We sought to determine the relationship between periprocedural antiplatelet/anticoagulant therapy and pocket haematoma formation in patients undergoing cardiac implantable electronic device (CIED) implantation. Methods We conducted a retrospective study including 232 consecutive patients undergoing CIED implantation in the department of cardiology of the Medipol University Hospital. Patients were divided into six groups: clopidogrel group (n = 12), acetylsalicylic acid (ASA) group (n = 73), ASA + clopidogrel group (n = 29), warfarin group (n = 34), warfarin + ASA group (n = 21) and no antiplatelet-anticoagulant therapy group as the control group (n = 63). CIED implantations were stratified under four subtitles including implantable cardioverter/defibrillator (ICD), cardiac resynchronization therapy (CRT), permanent pacemaker and the last group as either device upgrade or generator replacement. Results The mean age of the patients was 63 ± 14 years and 140 patients were male (60.3%). A pocket haematoma was documented in 6 of 232 patients (2.6%). None of the patients with pocket haematoma needed pocket exploration or blood transfusion. The type of the device did not have a significant effect on pocket haematoma incidence (P = 0.250). Univariate logistic regression showed that platelet level and ASA plus clopidogrel use were significantly associated with haematoma frequency after CIED implantations, respectively (OR: 0.977, CI 95% [0.958-0.996]; OR: 16.080, CI 95% [2.801-92.306]). Multivariate analysis revealed that dual antiplatelet treatment (ß = 3.016, P = 0.002, OR: 2.410, 95% CI [3.042-136.943]) and baseline platelet level (ß = -0.027, p:0.025, OR: 0.974, 95% CI [0.951-0.997]) were independent risk factors for pocket haematoma formation. Conclusion Dual antiplatelet therapy and low platelet levels significantly increased the risk of pocket haematoma formation in patients undergoing CIED implantations.

Myocardial injury biomarkers after radiofrequency catheter and cryoballoon ablation for atrial fibrillation and their impact on recurrence.

BACKGROUND: Myocardial injury induced by catheter ablation (CA) for atrial fibrillation (AF) leads to elevated biomarker levels. AIM: This prospective study examined levels of myocardial injury biomarkers (creatinine kinase [CK], myocardial bound for CK [CK-MB], and troponin I [TnI]) and their impact on AF recurrence following two different ablation strategies, namely: cryoballoon ablation (CBA) and radiofrequency ablation (RFA). We also aimed to evaluate the relationship between AF recurrence after CA and other clinical, echocardiographic and procedural parameters. METHODS: We enrolled 98 patients with AF, 21% of whom had persistent AF and 79% had paroxysmal AF. 58% of patients underwent CBA, and 42% underwent RFA. CK, CK-MB, and TnI levels were measured before and 6 h after the procedure. Patients had follow-up visits three, six, and nine months after the index procedure. Biomarker levels were compared between the patients with and without AF recurrence. RESULTS: Post-ablation CK (postCK), post-ablation CK-MB (postCKMB), and post-ablation TnI (postTnI) levels were significantly high in the CBA and RFA groups (p < 0.001 for all). TnI elevation (DTnI) was correlated with age (p = 0.033) and median temperature reached during ablation (p < 0.005) in the CBA group, while it was correlated with application time in the RFA group (p < 0.001). Multivariate analysis in the CBA group revealed age and left atrium diameter as positive independent predictors (p = 0.029 and p = 0.046), and DTnI as a negative independent predictor for AF recurrence (p = 0.001). Elevated cardiac biomarkers were not associated with AF recurrence in the RFA group (p > 0.05). CONCLUSIONS: The levels of all cardiac biomarkers were elevated after CBA and RFA. Elevated TnI levels after CBA were independent negative predictors of AF recurrence. Measurement of TnI levels after CBA may be useful for the prediction of better clinical outcome.

Successful radiofrequency pulmonary vein isolation in a patient with pneumonectomy.

Among electrophysiologic procedures, catheter ablation of atrial fibrillation (AF) is challenging, requiring the isolation of all pulmonary veins (PVs). AF is associated with serious complications including PV stenosis. Presently described was a technically challenging case of PV isolation in a patient with left-sided pneumonectomy due to lung cancer.

Predicting Ventricular Arrhythmias in Cardiac Resynchronization Therapy: The Impact of Persistent Electrical Dyssynchrony.

BACKGROUND: Although response to cardiac resynchronization therapy (CRT) has been conventionally assessed with left ventricular volume reduction, ventricular arrhythmias (ventricular tachycardia/ventricular fibrillation [VT/VF]) are of critical importance associated with unfavorable outcomes even in the "superresponders" to therapy. We evaluated the predictors of VT/VF and the association of residual dyssynchrony during follow-up. METHODS: Ninety-five patients receiving CRT were followed-up for 9 ± 3 months. Post-CRT dyssynchrony was defined as a prolonged QRS duration (QRSd) for persistent electrical dyssynchrony (ED), and a Yu index ≥ 33 ms for persistent mechanical dyssynchrony. The first VT/VF episode, including nonsustained VT detected on device interrogation and/or appropriate antitachycardia pacing or shock for VT/VF, were the end points of the study. RESULTS: Forty-five patients who reached the study end points had significantly lower mean ΔQRS (baseline QRSd - post-CRT QRSd) values than those without VT/VF (-20.8 ± 28.9 ms vs -6.6 ± 30.7 ms, P = 0.022). Both the baseline and post-CRT QRSds, along with the Yu index values, were not different in two groups. Patients with VT/VF were statistically more likely to have persistent ED (38% vs 9%, P = 0.021). Kaplan-Meier curves showed that a negative ΔQRS was associated with a higher incidence of VT/VF during follow-up (P = 0.016). A multivariate Cox model revealed that QRS prolongation was an independent predictor of VT/VF after CRT (P = 0.029). CONCLUSIONS: A negative ΔQRS, also called persistent ED, is associated with VT/VF. Narrowest possible QRSd might be a reliable goal of both implantation and optimization of devices to reduce arrhythmic events after CRT.

Asymptomatic Pulmonary Embolism after Ablation.

BACKGROUND: Pulmonary embolism (PE) is a life-threatening event with a broad presentation spectrum ranging from asymptomatic cases to sudden cardiac arrest. It is unclear if right atrial emboli cause PE in patients with atrial fibrillation (AF) or if mild PE itself increases right cardiac pressure provoking AF. OBJECTIVE: To determine the incidence and predictors of asymptomatic PE in patients undergoing AF ablation. METHOD AND RESULTS: Patients (n = 93) were screened and those with previous or current symptomatic PE or venous thromboembolism, pulmonary hypertension, increased right heart pressures detected on echocardiography, a history of stroke, transient ischemic attack, coagulopathy or cancer and inappropriate contrast for the evaluation of pulmonary arterial tree were excluded. The remaining AF patients (n = 71) underwent guided ablation controlled with 3-dimensional, left atrial and pulmonary venous computed tomography. The asymptomatic PE was defined by using the modified Miller score by 2 independent assessors in 6 patients. Univariate logistic regression showed that age (OR: 1.094, 95% CI 1.007-1.188, p = 0.033), diabetes (OR: 12.000, 95% CI 1.902-75.716, p = 0.008), CHA2DS2-VASc score (OR: 2.800, 95% CI 1.304-6.013, p = 0.008), and pulmonary artery diameter (OR: 1.221, 95% CI 1.033-1.444, p = 0.019) were significantly associated with PE. However, multivariate analysis revealed that the CHA2DS2-VASc score (p = 0.047) remained the exclusive significant predictor for asymptomatic PE. CONCLUSION: The incidence of random asymptomatic PE in AF patients is high (>8%). The CHA2DS2-VASc score can predict silent PE. Since patients with a high CHA2DS2-VASc score are already anticoagulated, our results do not change clinical practice but are noteworthy in terms of the cause-effect relationship between AF and PE.

Native Electrocardiographic QRS Duration after Cardiac Resynchronization Therapy: The Impact on Clinical Outcomes and Prognosis.

BACKGROUND: We investigated whether reversed electrical remodeling (RER), defined as narrowing of the native electrocardiographic QRS duration after cardiac resynchronization therapy (CRT), might predict prognosis and improvement in echocardiographic outcomes. METHODS AND RESULTS: A total of 110 CRT recipients were retrospectively analyzed for the end points of death and hospitalization during 18 ± 3 months. Native QRS durations were recorded at baseline and 6 months after CRT (when pacing was switched off to obtain an electrocardiogram) to determine RER. CRT response and mitral regurgitation (MR) improvement were defined as ≥15% reduction in left ventricular end-systolic volume and absolute reduction in regurgitant volume (RegV) at 6 months, respectively. Overall, 48 patients (44%) had RER, which was associated with functional improvement (77% vs 34%; P < .001) and CRT response (81% vs 52%; P < .001) compared with those without RER. The change in the intrinsic QRS duration correlated with the reduction in RegV (r = 0.51; P < .001) and in tenting area (r = 0.34; P < .001). RER was a predictor of MR improvement (P = .023), survival (P = .043), and event-free survival (P = .028) according to multivariate analyses. CONCLUSIONS: Narrowing of the intrinsic QRS duration is associated with functional and echocardiographic CRT response, reduction in MR, and favorable prognosis after CRT.

Changes in Electrocardiographic P Wave Parameters after Cryoballoon Ablation and Their Association with Atrial Fibrillation Recurrence.

BACKGROUND: Changes in P wave parameters after circumferential pulmonary vein isolation (CPVI) have been previously identified. In this study, we aimed to determine the changes in P wave parameters surface electrocardiogram (ECG) after cryoballoon ablation (CBA) for atrial fibrillation (AF) and evaluate their relationship with AF recurrence. METHODS: Sixty-one patients (mean age 53 ± 11 years, 50.8% male) with paroxysmal AF who underwent CBA were enrolled. A surface ECG was obtained from all patients immediately before the procedure, and repeated 12 hours after the procedure. P wave amplitude (Pamp), P wave duration (Pwd), and P wave dispersion (Pdis) values in preprocedural and postprocedural ECGs were measured and compared. Recurrence rates of AF in 3, 6, and 9 months following ablation were recorded for all patients. Changes in P wave parameters were compared between patients with and without AF recurrence. RESULTS: Compared to preprocedural measurements, Pamp (from 0.58 ± 0.18 mV at baseline to 0.48 ± 0.17 mV, P < 0.001), Pwd (from 109.72 ± 18.43 ms at baseline to 91.36 ± 22.53 ms, P < 0.001), and Pdis (from 55.44 ± 20.45 ms at baseline to 45.30 ± 15.31 ms, P < 0.001) were significantly decreased after CBA. The difference in Pamp between pre- and postprocedural values (∆Pamp) was significantly higher in patients without AF recurrence compared to those with recurrence (0.10 ± 0.06 mV vs 0.04 ± 0.01 mV, P = 0.002). There was no difference in Pwd difference (∆Pwd) and Pdis difference (∆Pdis) between patients with and without AF recurrence (P > 0.05). CONCLUSION: Pamp, Pwd, and Pdis parameters exhibited significant decrease after CBA compared to preprocedural measurements. Decreased Pamp was shown to be a predictor for good clinical outcomes following CBA.

Adjusting the QRS Duration by Body Mass Index for Prediction of Response to Cardiac Resynchronization Therapy: Does One QRS Size Fit All?

BACKGROUND: QRS duration (QRSd) is known to be affected by body weight and length. We tested the hypothesis that adjusting the QRSd by body mass index (BMI) may provide individualization for patient selection and improve prediction of cardiac resynchronization therapy (CRT) response. METHODS: A total of 125 CRT recipients was analyzed to assess functional (≥1 grade reduction in NYHA class) and echocardiographic (≥15% reduction in LVESV) response to CRT at 6 months of implantation. Baseline QRSd was adjusted by BMI to create a QRS index (QRSd/BMI) and tested for prediction of CRT response in comparison to QRSd. RESULTS: Overall, 81 patients (65%) responded to CRT volumetrically. The mean QRS index was higher in CRT responders compared to nonresponders (6.2 ± 1.1 vs 5.2 ± 0.8 ms.m(2) /kg, P < 0.001). There was a positive linear correlation between the QRS index and the change in LVESV (r = 0.487, P < 0.001). Patients with a high QRS index (≥5.5 ms.m(2) /kg, derived from the ROC analysis, AUC = 0.787) compared to those with a prolonged QRSd (≥150 ms, AUC = 0.729) had a greater functional (72% vs 28%, P < 0.001) and echocardiographic (80% vs 44%, P < 0.001) improvement at 6 months. QRS index predicted CRT response at regression analysis. CONCLUSIONS: Indexing the QRSd by BMI improves patient selection for CRT by eliminating the influence of body weight and length on QRSd. QRS index is a novel indicator that provides promising results for prediction of CRT response.

Effect of QRS Narrowing After Cardiac Resynchronization Therapy on Functional Mitral Regurgitation in Patients With Systolic Heart Failure.

The determinants of improvement in functional mitral regurgitation (FMR) after cardiac resynchronization therapy (CRT) remain unclear. We evaluated the predictors of FMR improvement and hypothesized that CRT-induced change in QRS duration (ΔQRS) might have an impact on FMR response after CRT. One hundred ten CRT recipients were enrolled. CRT response (≥ 15 reduction in left ventricular end-systolic volume) and FMR response (absolute reduction in FMR volume) were assessed with echocardiography before and 6 months after CRT. The study end points included all-cause death or hospitalization assessed in 12 ± 3 months (range 1 to 18). A total of 71 patients (65%) responded to CRT at 6 months. FMR response was observed in 49 (69%) of the CRT responders and 8 (20%) of the CRT nonresponders (p <0.001). Although the baseline QRS durations were similar, the paced QRS durations were shorter (p = 0.012) and the ΔQRS values were greater (p = 0.003) in FMR responders compared with FMR nonresponders. There was a linear correlation between ΔQRS and change in regurgitant volume (r = 0.49, p <0.001). At multivariate analysis, baseline tenting area (p = 0.012) and ΔQRS (p = 0.028) independently predicted FMR response. A ΔQRS ≥ 20 ms was related to CRT response, FMR improvement, and lower rates of death or hospitalization during follow-up (p values <0.05). In conclusion, QRS narrowing after CRT independently predicts FMR response. A ΔQRS ≥ 20 ms after CRT is associated with a favorable outcome in all clinical end points.

QRS prolongation after cardiac resynchronization therapy is a predictor of persistent mechanical dyssynchrony.

PURPOSE: Prolonged QRS duration is the main selection criterion for cardiac resynchronization therapy (CRT) which ameliorates left ventricular mechanical dyssynchrony (MD). However, consequences of post-CRT QRS prolongation and residual MD have been poorly evaluated. We aimed to define the predictors of persistent MD and hypothesized that CRT-induced QRS change (ΔQRS) might have an impact on residual MD after CRT. METHODS: A total of 80 patients receiving CRT were included in the study. ΔQRS was calculated as the difference between the baseline and paced QRS intervals. Residual MD was assessed early after device implantation with a longitudinal dyssynchrony index (Yu index). Significant MD was defined as a Yu index ≥ 33 msec. Two groups were created based on residual MD and compared according to clinical, electrocardiographic and echocardiographic features. RESULTS: Patients with persistent MD had longer paced QRS durations (182.5 ± 16.2 vs. 165.4 ± 22.5 msec, p = 0.03) and were less likely to have left ventricular (LV) leads located in the posterolateral vein (53 % vs. 85 %, p = 0.002). The linear correlation between the ΔQRS and the Yu index values was modest (Spearman's rho = -0.341, p = 0.002); additionally, a prolonged QRS was strongly associated with MD after CRT (p = 0.00008). Both LV lead localization and CRT-induced QRS prolongation emerged as the significant predictors of persistent MD. A biventricularly paced QRS more than 10 msec longer than the pre-paced QRS width was predictive of persistent MD after CRT (sensitivity = 80 %, specificity = 62 %). CONCLUSIONS: ΔQRS was found to be associated with residual MD after CRT. Ten milliseconds of QRS prolongation predicted persistent MD after CRT.

Prolonged Tp-e Interval, Tp-e/QT Ratio and Tp-e/QTc Ratio in Patients with Type 2 Diabetes Mellitus.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is associated with increased risk of malignant ventricular arrhythmias. Cardiac electrical inhomogeneity may be the leading cause of the increased arrhythmic risk in patients with T2DM. The peak and the end of the T wave (Tp-e) interval and associated Tp-e/QT ratio are promising measures of ventricular repolarization indicating transmural dispersion of repolarization. The aim of this study was to assess ventricular repolarization in patients with T2DM by using Tp-e interval, Tp-e/QT ratio and Tp-e/corrected QT interval (QTc) ratio. METHODS: Forty-three patients with T2DM and 43 healthy control subjects, matched by gender and age, were studied. All participants underwent electrocardiography (ECG) recording. PR, RR and QT intervals represents the ECG intervals. These are not abbreviations. In all literature these ECG intervals are written like in this text. Tp-e intervals were measured from 12-lead ECG. Rate QTc was calculated by using the Bazett's formula. Tp-e/QT ratio and Tp-e/QTc ratio were also calculated. RESULTS: Mean Tp-e interval was significantly prolonged in patients with T2DM compared to controls (79.4±10.3, 66.4±8.1 ms, respectively; P<0.001). We also found significantly higher values of Tp-e/QT ratio and Tp-e/QTc ratio in patients with diabetes than controls (0.21±0.03, 0.17±0.02 and 0.19±0.02, 0.16±0.02, respectively; P<0.001). There was no difference in terms of the other ECG parameters between the groups. CONCLUSION: Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio were prolonged in patients with T2DM. We concluded that T2DM leads to augmentation of transmural dispersion of repolarization suggesting increased risk for ventricular arrhythmogenesis.