Clinical role of post-angioplasty hyperemic microvascular resistances in chronic ischemic left ventricular dysfunction.

AIMS: To investigate the impact of hyperemic microvascular resistances (HMRs) on myocardial perfusion and contractility after percutaneous coronary intervention (PCI) in chronic ischemic left ventricular dysfunction (CILVD). METHODS: The current retrospective study included 48 patients with CILVD of the left anterior descending territory undergoing HMRs assessment before and after PCI with a dual-sensor intracoronary pressure-flow wire. The severity of resting myocardial underperfusion and contractile dysfunction of the left anterior descending territory was scored as summed rest score (SRS-T) by single photon emission tomography, wall motion score index (WMSI-T) and left ventricular ejection fraction (LVEF) by transthoracic echocardiography before PCI and after 3 months. Patients were divided into two groups according to the mean post-PCI HMRs. RESULTS: Mean post-PCI HMRs were 2.05 ±â€Š0.43 mmHg/cm/s; increased HMRs (i.e. >2 mmHg/cm/s) were found in 17 patients (35.4%, group B) (3.29 ±â€Š0.77 mmHg/cm/s), whereas 31 patients (64.6%, group A) showed lower values (1.35 ±â€Š0.34 mmHg/cm/s; P < 0.001). Pre-PCI HMRs, WMSI-T and SRS-T were similar among groups.After PCI, a significant improvement of LVEF, WMSI-T and SRS-T was observed only in group A (6.6 ±â€Š7.4%, 0.44 ±â€Š0.42 and 3.9 ±â€Š2.9, respectively) compared with group B (1.3 ±â€Š1.9%, 0.02 ±â€Š0.07 and 1.1 ±â€Š1.9; P = 0.011, P < 0.001 and P = 0.028, respectively).Post-PCI HMRs predicted the absence of improvement of LVEF and WMSI-T at a cutoff value of 1.95 mmHg/cm/s (area under the curve 0.69 and 0.73; P = 0.038 and 0.017, respectively), with a positive predictive value of 96 and 100%, respectively. CONCLUSION: Increased post-PCI HMRs may predict the lack of functional improvement of the revascularized myocardium in CILVD.

Agenesia of the left atrial appendage: possible but very rare.

: Agenesia of the left atrial appendage in a patient with atrial fibrillation is shown. Although of interest, the prevalence of this abnormality is very low.

Electroanatomic mapping and ablation of macroreentrant atrial tachycardia: comparison between successfully and unsuccessfully treated cases.

INTRODUCTION: Ablation of macroreentrant atrial tachycardia (MRAT) is demanding and identification of predictors of failure may be of help in patient management. This study compares the characteristics of successfully versus unsuccessfully treated patients undergoing electroanatomic mapping (EAM) and ablation of MRAT. METHODS AND RESULTS: Consecutive patients undergoing EAM and ablation of MRAT were included. Ablation was linearly placed at the mid-diastolic isthmus (MDI) to achieve arrhythmia interruption and conduction block. Variables were analyzed for predictors of both procedural failure and cumulative failure (procedural failure + early recurrences). Fifty-two patients (37 M; age 64 +/- 16 years) with 56 MRATs were considered. The MRAT was in the right atrium in 25 morphologies (45%) and 32 (57%) showed a double-loop reentry. Fifty-one morphologies (91%) in 47 patients were successfully treated; 3 patients had early recurrences of the same MRAT. None of the clinical variables considered significantly differed in the successfully treated group as compared to the unsuccessfully treated. Conversely, there was a significant difference as to the EAM characteristics: successfully treated cases showed a narrower target isthmus with a lower voltage amplitude and slower conduction velocity (CV). In the MDI, a CV >60 cm/sec and a width >40 mm were the strongest predictors of procedural failure and cumulative failure, respectively. CONCLUSIONS: In this patient population, while the clinical variables did not differ significantly, there was a significant difference in the EAM characteristics between successfully and unsuccessfully treated cases. CV and width of the isthmus target for ablation were the strongest independent predictors of procedure outcome.

[PROVA E TRASPORTA Project: results of tele-transmission of the electrocardiogram from community hospitals and emergency service ambulances in the management of ST-elevation acute coronary syndromes]. / Progetto PROVA E TRASPORTA: rete territoriale di teletrasmissione dell'elettrocardiogramma da postazioni fisse e ambulanze Bls. Utilità nella gestione della sindrome coronarica acuta con sopraslivellamento del tratto ST.

BACKGROUND: Availability of a telematic system of electrocardiogram (ECG) transmission may improve the management of ST-elevation myocardial infarction (STEMI), by reducing time to treatment. The aim of this study was to show the effectiveness of telephone transmission of ECG in improving quality of care for patients with acute STEMI. METHODS: Since January 1, 2003, we activated a management program of STEMI in healthcare district of Varese, located in the North-West of Lombardy (Italy), comprising one fourth-level hospital, equipped with a cath lab on call 24/24 h for primary angioplasty since 1993 and cardiac surgery, and 2 community hospitals, placed in a mountain area approximately 30 km far from Varese. The emergency medical system (EMS) transport was activated 24/24 h and has 15 basic life support (BLS) ambulances with trained nurse staff and 2 mobile units with medical staff, all of them equipped with semiautomatic defibrillator Lifepack 12, enabling a GSM telephone transmission of a 12-lead ECG, coupled with 3-lead continuous rhythm recording and clinical data, if necessary. The ECGs were transmitted to a core unit placed in the coronary care unit (CCU) of the Hospital di Circolo of Varese, directly connected with the EMS core unit. RESULTS: From January 2003 to August 2005, a total of 2063 ECGs were transmitted, 538 of them (26%) recorded by EMS ambulances. Of 144 ECGs (7%) showing a persistent ST-elevation suggesting an acute STEMI (group A), 112 subjects underwent reperfusion: 73 were treated with angioplasty and 39 by lysis alone. By comparing data of group A with a group of 256 patients (180 reperfused) with acute STEMI, admitted to our hospital in the same period without ECG teletransmission (group B), we observed no statistical difference in mortality and reperfusion rates but a significative reduction in the pre-hospital and in-hospital times in group A patients treated by primary angioplasty and thrombolysis. CONCLUSIONS: Our study confirms previous results in that an early availability of a 12-lead ECG, transmitted from peripheral community hospitals and BLS ambulances, is able to reduce time to management of patients with an acute STEMI, thus improving quality of decision-making and treatment.

Predictive significance for sudden death of microvolt-level T wave alternans in New York Heart Association class II congestive heart failure patients: a prospective study.

BACKGROUND: Sudden cardiac death (SDC) is responsible for approximately 60-70% of deaths in New York Heart Association (NYHA) class II congestive heart failure (CHF) patients. Recently, microvolt-level T wave alternans has been proposed as a new noninvasive tool to identify CHF patients at risk for SCD and ventricular tachycardia/fibrillation (VT/VF). OBJECTIVES: To determine the prognostic value of MTWA in NYHA class II patients. METHODS: Among 181 consecutive CHF patients with ischemic and nonischemic cardiomyopathy, 73 patients in NYHA class II with left ventricular ejection fraction <45% were selected and prospectively investigated. MTWA was determined during bicycle exercise testing. The study end point was defined as SCD, documented sustained VT/VF and appropriate implantable cardioverter defibrillator (ICD) shock. RESULTS: MTWA was positive in 30 (41%) patients, negative in 26(36%) patients and indeterminate in 17 (23%) patients. During an average follow-up of 17.1+/-7.4 months, seven patients had an arrhythmic event in the MTWA positive group, whereas one and no events occurred in the indeterminate and negative group, respectively. From Kaplan-Meier univariate analysis and multivariate Cox analysis, MTWA was a significant arrhythmic risk stratifier (p=0.01 and p=0.03, respectively). Sensitivity, specificity, negative and positive predictive values of MTWA were 100%, 53%, 100% and 24%, respectively. CONCLUSION: Our data suggest that MTWA is a promising predictor of arrhythmic events in NYHA class II CHF patients.