Risk of pacemaker implantation after uneventful successful cavotricuspid isthmus radiofrequency ablation in patients with common atrial flutter.

INTRODUCTION: Little is known about the risk of pacemaker implantation after common atrial flutter ablation in the long-term. METHODS: We retrospectively reviewed the electrophysiology laboratory database at two Spanish University Hospitals from 1998 to 2012 to identify patients who had undergone successful ablation for cavotricuspid dependent atrial flutter. Cox regression analysis was used to examine the risk of pacemaker implantation. RESULTS: A total of 298 patients were considered eligible for inclusion. The mean age of the enrolled patients was 65.7±11. During 57.7±42.8 months, 30 patients (10.1%) underwent pacemaker implantation. In the stepwise multivariate models only heart rate at the time of the ablation (OR: 0.96; 95% CI: 0.93-0.98; p<0.0001) and intraventricular conduction disturbances in the baseline ECG (OR: 3.87; 95% CI: 1.54-9.70; p=0.004) were independents predictors of the need of pacemaker implantation. A heart rate of ≤65 bpm was identified as the optimal cut-off value to predict the need of pacemaker implantation in the follow-up (sensitivity: 79%, specificity: 74%) by ROC curve analyses. CONCLUSION: This is the first study of an association between the slow conducting common atrial flutter and subsequent risk of pacemaker implantation. In light of these findings, assessing it prior to ablation can be helpful for the risk stratification of sinus node disease or atrioventricular conduction disease requiring a pacemaker implantation in patients with persistent atrial flutter.

[Electrical storm in patients with prophylactic defibrillator implantation]. / Evolución de los pacientes portadores de desfibrilador como prevención primaria tras un episodio de tormenta arrítmica.

INTRODUCTION: Little is known about the prevalence of electrical storm, baseline characteristics and mortality implications of patients with implantable cardioverter defibrillator in primary prevention versus those patients without electrical storm. We sought to assess the prevalence, baseline risk profile and survival significance of electrical storm in patients with implantable defibrillator for primary prevention. METHODS: Retrospective multicenter study performed in 15 Spanish hospitals. Consecutives patients referred for desfibrillator implantation, with or without left ventricular lead (at least those performed in 2010 and 2011), were included. RESULTS: Over all 1,174 patients, 34 (2,9%) presented an electrical storm, mainly due to ventricular tachycardia (82.4%). There were no significant baseline differences between groups, with similar punctuation in the mortality risk scores (SHOCKED, MADIT and FADES). A clear trigger was identified in 47% of the events. During the study period (38±21 months), long-term total mortality (58.8% versus 14.4%, p<0.001) and cardiac mortality (52.9% versus 8.6%, p<0.001) were both increased among electrical storm patients. Rate of inappropriate desfibrillator intervention was also higher (14.7 versus 8.6%, p<0.001). CONCLUSIONS: In the present study of patients with desfibrillator implantation for primary prevention, prevalence of electrical storm was 2.9%. There were no baseline differences in the cardiovascular risk profile versus those without electrical storm. However, all cause mortality and cardiovascular mortality was increased in these patients versus control desfibrillator patients without electrical storm, as was the rate of inappropriate desfibrillator intervention.

Secondary forms of Takotsubo cardiomyopathy: A whole different prognosis.

BACKGROUND: Takotsubo syndrome (TKS) usually mimics an acute coronary syndrome. However, several clinical forms have been reported. Our aim was to assess if different stressful triggers had prognostic influence on TKS, and to establish a working classification. METHODS: We performed an analysis including patients with TKS between 2003-2013 from our prospective local database and the RETAKO National Registry, fulfilling Mayo criteria. Patients were divided in two groups regarding their potential triggers: (a) none/psychic stress as 'primary forms' and (b) physical factors (asthma, surgery, trauma, etc.) as 'secondary forms'. RESULTS: Finally, 328 patients were included, 90.2% women, with a mean age of 69.7 years. Patients were divided into primary TKS (n=265) and 63 secondary TKS groups. Age, gender, previous functional class and cardiovascular risk profile displayed no differences between groups before admission. However, primary-TKS patients suffered a main complaint of chest pain (89.4% vs 50.7%, p<0.0001) with frequent vegetative symptoms. Regarding treatment before admission, there were no differences either. During admission, differences were related to more intensive antithrombotic and anxiolytic drug use in the primary TKS group. Inotropic and mechanical ventilation use was higher in the secondary cohort. After discharge, a more frequent prescription of beta-blockers and statins in primary-TKS patients was seen. Secondary forms displayed more in-hospital stay and evolutive complications: death (hazard ratio (HR): 3.41; 95% confidence interval (CI): 1.14-10.16, p=0.02), combined event variable (MACE) (HR: 1.61; 95% CI: 1.01-2.6, p=0.04) and recurrences (HR: 1.85; 95% CI: 1.06-3.22, p=0.02). CONCLUSION: Secondary TKS could present or mark worse short and long-term prognoses in terms of mortality, recurrences and readmissions. We propose a simple working nomenclature for TKS.

Analyses of inappropriate shocks in a Spanish ICD primary prevention population: Predictors and prognoses.

BACKGROUND: ICDs have been demonstrated to be highly effective in the primary prevention of sudden death, but inappropriate shocks (IS) occur frequently and represent one of the most important adverse effects of ICDs. The aim of this study was to analyze IS and identify the clinical predictors and prognostic implications of ISs in a real-world primary prevention ICD population. METHODS: This multicenter retrospective study was performed in 13 centers with experience in the field of ICD implantation (at least 30 per year) and ICD follow-up in Spain. All consecutive patients who underwent ICD implantation for primary prevention between January 2008 and May 2014 were included. RESULTS: One-thousand-sixteen patients were included, and 4 (0.39%) were lost to follow-up. Two-hundred-seventeen (21.4%) patients suffered from shock; 69 (6.8%) of these patients experienced IS, and 154 (15.4%) experienced appropriate shocks (AS). Age (<65 years, hazard ratio (HR) 2.588 [95% CI 1.282-5.225]; p=0.008), history of atrial fibrillation (HR 2.252 [95% CI 1.230-4.115]; p=0.009), non-ischemic myocardiopathy (HR 2.258 [95% CI 1.090-4.479]; p=0.028), and cardiac resynchronization therapy (HR 0.385 [95% CI 0.200-0.740]; p=0.004) were identified as IS predictors in a multivariate analysis. IS was not associated with rehospitalization due to heart failure, myocardial infarction, cardiovascular mortality or all-cause mortality. CONCLUSIONS: This analysis of our national registry identified the independent IS predictors of age, atrial fibrillation history and cardiac resynchronization therapy and suggests that ISs are not linked to poorer clinical endpoints.

Relative performance of three formulas to assess renal function at predicting in-hospital hemorrhagic complications in an acute coronary syndrome population. What does the new CKD-EPI formula provide?

AIMS: Assessment of renal function is important for bleeding risk stratification in acute coronary syndrome (ACS). There are three formulas routinely used to assess renal function: the Cockroft-Gault (C-G) formula, the MDRD-4 formula and the new Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Our aim was to compare the ability of these formulas to predict the risk of in-hospital bleeding in patients with ACS. METHODS: The study included 3270 patients with ACS. The performance of each formula with respect to in-hospital TIMI (Thrombolysis In Myocardial Infarction) major or TIMI minor bleeding were assessed using continuous data and by dividing patients into four subgroups according to the estimated glomerular filtration rate (eGFR): ≥90, 89-60, 30-59 and <30 ml/min/1.73 m(2). RESULTS: Bleeding predictive ability was significantly higher for the C-G formula than for MDRD-4 and CKD-EPI formulas, as evaluated by the area under the curve (AUC); continuous eGFR AUCs: 0.73, 0.69 and 0.71, respectively; categorical eGFR AUCs: 0.71, 0.66 and 0.68, respectively. Net reclassification improvement based on the eGFR categories was significantly positively favored C-G: 9.5% (95% confidence interval (CI) 1.8-17.2%) and 19.1% (95% CI 11.3-26.9%) compared with CKD-EPI and MDRD-4, respectively. After multivariable adjustment, the C-G formula predicted in-hospital bleeding better than MDRD-4 formula (severe renal dysfunction vs. normal renal function: odds ratio 7.98, 95% CI 2.61-24.38 with C-G; odds ratio 3.76, 95% CI 1.63-8.69 with MDRD-4; and odds ratio 5.77, 95% CI 2.18-15.24 with CKD-EPI. CONCLUSIONS: Our findings suggest that the C-G eGFR may improve risk prediction of in-hospital bleeding more than the MDRD-4 equation and the new CKD-EPI equation in patients with ACS.

Walking beyond the GRACE (Global Registry of Acute Coronary Events) model in the death risk stratification during hospitalization in patients with acute coronary syndrome: what do the AR-G (ACTION [Acute Coronary Treatment and Intervention Outcomes Network] Registry and GWTG [Get With the Guidelines] Database), NCDR (National Cardiovascular Data Registry), and EuroHeart Risk Scores Provide?

OBJECTIVES: This study sought to compare the in-hospital prognostic values of the original and updated GRACE (Global Registry of Acute Coronary Events) risk score (RS) and the AR-G (ACTION [Acute Coronary Treatment and Intervention Outcomes Network] Registry and the GWTG [Get With the Guidelines] Database) RS in acute coronary syndromes (ACS). To evaluate the utility of recalculating risk after percutaneous coronary intervention (PCI) with newer RS models (NCDR [National Cardiovascular Data Registry] and EHS [EuroHeart Score] RS). BACKGROUND: Defined in 2003, GRACE is among the most popular systems of risk stratification in ACS. An updated version of GRACE has since appeared and new RS have been developed, aiming to improve risk prediction. METHODS: From 2004 to 2010, 4,497 consecutive patients admitted to a single center in Spain with an ACS were included (32.1% ST-segment elevation myocardial infarction, 19.2% unstable angina). Discrimination (C-statistic) and calibration (Hosmer-Lemeshow [HL]) indexes were used to assess performance of each RS. A comparative analysis of RS designed to predict post-PCI mortality NCDR and EHS RS versus the GRACE and AR-G RS was performed in a subgroup of 1,113 consecutive patients included in the study. RESULTS: There were 265 in-hospital deaths (5.9%). Original and updated GRACE RS and the AR-G RS all demonstrated good discrimination for in-hospital death (C-statistics: 0.91, 0.90 and 0.90, respectively) with optimal calibration (HL p: 0.42, 0.50, and 0.47, respectively) in all spectra of ACS, according to different managements (PCI vs. conservative) and without significant differences between the 3 different RS. In patients undergoing PCI, EHS and NCDR RS (C-statistic = 0.80 and 0.84, respectively) were not superior to GRACE RS (C-statistic = 0.91), albeit in the subgroup of patients undergoing PCI who were categorized as high risk using the GRACE RS, both EHS and NCDR have contributed to decrease the false positive rate generated by using the GRACE RS. CONCLUSIONS: Despite having been developed over 8 years ago, the GRACE RS still maintains its excellent performance for predicting in-hospital risk of death among ACS patients.

Comparing the predictive validity of three contemporary bleeding risk scores in acute coronary syndrome.

AIMS: Haemorrhagic complications are strongly linked with adverse outcomes in acute coronary syndrome (ACS) patients. Various risk scores (RS) are available to predict bleeding risk in these patients. We compared the performance of three contemporary bleeding RS in ACS. METHODS: We studied 4500 consecutive patients with ACS. We calculated the ACTION, CRUSADE, and Mehran et al. (2010) bleeding RS, and evaluated their performance for predicting their own major bleeding events and TIMI serious (major or minor) bleeding episodes, in patients with either non-ST-elevation ACS (NSTEACS) or ST-elevation myocardial infarction (STEMI). Calibration (Hosmer-Lemeshow test, HL) and discrimination (c-statistic) for the three RS were computed and compared. RESULTS: For RS-specific major bleeding, ACTION and CRUSADE showed the best prognostic discrimination in STEMI (c=0.734 and 0.791, respectively; p=0.04), and in NSTEACS (c=0.791 and 0.810; p=0.4); being CRUSADE significantly superior to Mehran et al. in both ACS types (p<0.05). All RS performed well in patients undergoing coronary arteriography using either a radial or femoral approach (all c≥0.718); however, their discriminative capacity was modest in patients not undergoing coronary arteriography and in those previously on oral anticoagulant (all c<0.70). For TIMI serious bleeding, ACTION and CRUSADE displayed the highest c-index values in both STEMI (0.724 and 0.703, respectively; p=0.3) and NSTEACS (c=0.733 and 0.744, respectively; p=0.6); however, calibration of ACTION was poor in both ACS types (HL p<0.05). CONCLUSIONS: Of contemporary bleeding RS, the CRUSADE score was found to be the most accurate quantitative tool for NSTEACS and STEMI patients undergoing coronary arteriography.