Combined electrical and global markers of dyssynchrony predict clinical response to cardiac resynchronization therapy.

AIM: To assess potential additional value of global left ventricular (LV) dyssynchrony markers in predicting cardiac resynchronization therapy (CRT) response in heart failure (HF) patients. METHODS: We included 103 HF patients (mean age 67 ± 12 years, 83% male) who fulfilled the guidelines criteria for CRT treatment. All patients had undergone full clinical assessment, NT-proBNP and echocardiographic examination. Global LV dyssynchrony was assessed using total isovolumic time (t-IVT) and Tei index. On the basis of reduction in the NYHA class after CRT, patients were divided into responders and non-responders. RESULTS: Prolonged t-IVT [0.878 (range, 0.802-0.962), p = 0.005], long QRS duration [0.978 (range, 0.960-0.996), p = 0.02] and high tricuspid regurgitation pressure drop [1.047 (range, 1.001-1.096), p = 0.046] independently predicted response to CRT. A t-IVT ≥ 11.6 s/min was 67% sensitive and 62% specific (AUC 0.69, p = 0.001) in predicting CRT response. Respective values for a QRS ≥ 151 ms were 66% and 62% (AUC 0.65, p = 0.01). Combining the two variables had higher specificity (88%) in predicting CRT response. In atrial fibrillation (AF) patients, only prolonged t-IVT [0.690 (range, 0.509-0.937), p = 0.03] independently predicted CRT response. CONCLUSION: Combining prolonged t-IVT and the conventionally used broad QRS duration has a significantly higher specificity in identifying patients likely to respond to CRT. Moreover, in AF patients, only prolonged t-IVT independently predicted CRT response.

Right ventricular lead positioning does not influence the benefits of cardiac resynchronization therapy in patients with heart failure and atrial fibrillation.

AIMS: Little is known about the optimal right ventricular (RV) pacing site in cardiac resynchronization therapy (CRT). This study compares bi-ventricular pacing at the left ventricular (LV) free wall combined with two different RV stimulation sites: RV outflow tract (RVOT+LV) vs. RV-apex (RVA+LV). METHODS AND RESULTS: Thirty-three patients (32 males) with chronic heart failure, NYHA class III-IV, optimal drug therapy, QRS-duration ≥150 ms, and chronic atrial fibrillation (AF) received CRT with two different RV leads, in the apex (RVA) or outflow tract (RVOT), together with an LV lead, all connected to a bi-ventricular pacemaker. Randomization to pacing in RVOT+LV or RVA+LV was made 1 month after implantation and cross-over to the alternate pacing configuration occurred after 3 months. The median age of patients was 69 ± 10 years, the mean QRS was 179 ± 23 ms, and 58% of patients had ischaemic heart disease. Seven patients had pacemaker rhythm at inclusion and 60% were treated with atrioventricular-junctional ablation before randomization. In the RVA+LV and RVOT+LV pacing modes, 67 and 63% (nonsignificant) responded symptomatically with a decrease of at least 10 points in the Minnesota Living with Heart Failure score. The secondary end-points (6-min walk test, peak oxygen uptake, N-Terminal fragment of B-type Natriuretic Peptide, and left ventricular ejection fraction) showed significant improvement between baseline and CRT, but not between RVOT+LV and RVA+LV. CONCLUSION: In this randomized controlled study, the exact RV pacing site, either apex or outflow tract, did not influence the benefits of CRT in a group of patients with chronic heart failure and AF. ClinicalTrials.gov ID: NCT00457834.

U22, a protocol to quantify symptoms associated with supraventricular tachycardia.

BACKGROUND: The main indication for ablation of supraventricular tachyarrhythmias (SVTA) is symptomatic relief. Specific paroxysmal symptoms cannot be quantified with general measures of quality of life, such as with the SF-36 questionnaire. U22 is a new protocol which measures the effects of arrhythmia on well-being, the intensity of discomfort during an episode, the type and temporal characteristics of dominant symptoms, and the duration and frequency of episodes. Discrete 0-10 scales are used. Unlike SF-36, U22 can be used in individual patients. METHODS: U22 and SF-36 protocols were used in the symptomatic evaluation of 88 patients (mean age = 49.6 +/- 16.4 years; 43 men), who underwent catheter ablation of SVTA. RESULTS: The U22 scores (SD) for (a) well-being (10 being best), (b) effects of arrhythmia on well-being (10 being worst), and (c) discomfort during arrhythmia (10 being worst) were 5.6 (2.7), 7.5 (2.8), and 8.0 (2.4), respectively. For comparison, the physical and mental component summaries of SF-36 were 45.3 (11.0) and 45.2 (12.1), respectively, slightly lower than the expected normal of 50. The intensity of dominant symptom scored by U22 was 9.7 (1.2), 10 being worst. In 29% of patients > or =4 symptoms were equally dominant. Multiple dominant symptoms in U22 were associated with a low general well-being in SF-36. CONCLUSION: We found U22 useful to quantify symptoms associated with SVTA.

U22 protocol as measure of symptomatic improvement after catheter ablation of atrial fibrillation.

INTRODUCTION: Left atrial catheter ablation is useful as symptomatic treatment in selected patients with atrial fibrillation (AF). Evaluation requires measurement of arrhythmia-related symptoms. Many of the published protocols have drawbacks and have been used in AF only, with no possible comparison to other ablations that compete for the same resources. U22 is a published protocol that quantifies paroxysmal tachycardia symptoms through scales with 11 answer alternatives, translated into discrete numerical scales 0-10. It has been shown to reflect the clinical improvement after ablation of supraventricular tachycardia. Here we report the use of U22 in measuring improvement after catheter ablation for AF. MATERIAL AND METHODS: A total of 105 patients underwent first-time ablation for AF and answered U22 and SF-36 forms at baseline and follow-up 304 (SD 121) days after ablation. Independently, the patients underwent a clinical follow-up. All decisions regarding medication and reablation were taken without knowledge of the symptom scores. Results. The U22 scores for well-being, arrhythmia as cause for impaired well-being, derived time-aspect score for arrhythmia, and discomfort during attack detected relevant improvements of symptoms after the ablation. U22 showed larger improvement in patients undergoing only one procedure than in patients who later underwent repeated interventions, thus reflecting the independent clinical decision for reablation. CONCLUSION: U22 quantifies the symptomatic improvement after AF ablation with adequate internal consistency and construct validity. U22 mirrors aspects of the arrhythmia symptomatology other than SF-36.

Symptomatic improvement after catheter ablation of supraventricular tachycardia measured by the arrhythmia-specific questionnaire U22.

INTRODUCTION: The main indication for ablation of supraventricular tachycardia is symptomatic relief. Generic measures of quality of life are not suitable for direct evaluation of arrhythmia-related symptoms, and a specific tool is needed. The questionnaire U22 quantifies symptoms associated with arrhythmic events. It uses discrete 0-10 scales for quantification of influence of arrhythmia on well-being, intensity of discomfort, type of dominant symptom, and a time aspect that summarizes duration and frequency of spells. We evaluated U22 in a well defined group of patients with paroxysmal supraventricular tachycardia, undergoing an intervention with a distinct end-point and a high success rate. METHODS: Symptoms in patients with accessory pathway and atrioventricular nodal re-entrant tachycardia scheduled for ablation were measured with U22 and SF-36 on admission. The evaluation was repeated after 6 months. RESULTS: Altogether 58 patients successfully ablated in 2006-2008 completed the four forms (U22 and SF-36 at base-line and follow-up, 210 ± 35 days after ablation). The score for well-being (0-10; 10 being best) increased from 5.9 ± 2.6 to 7.9 ± 1.9 (P < 0.0005). The score for arrhythmia as cause for impairment in well-being (0-10; 10 being highest) decreased from 7.5 ± 2.8 to 2.0 ± 3.1 (P < 0.0005). The time aspect score (0-10) decreased from 4.7 ± 1.5 to 1.4 ± 1.8 (P < 0.0005). The two SF-36 summary measures PCS and MCS increased from 46.9 ± 9.4 to 48.4 ± 10.7 and from 44.9 ± 12.5 to 49.1 ± 9.9 (P = 0.04 and 0.002). CONCLUSION: After successful ablation of accessory pathway and atrioventricular nodal re-entrant tachycardia, the U22 protocol detected a relevant increase in arrhythmia-related well-being. Modest improvement in general well-being was detected by the SF-36 protocol.

Long-term follow-up of patients treated with ICD: benefit in patients with preserved left ventricular function.

OBJECTIVE: Most major defibrillator trials have short follow-up and may neither capture the benefit for those with preserved function nor the progressive nature of advanced heart disease. We intended to investigate the long-term outcome in an unselected population of patients treated with ICD. DESIGN: We followed 124 consecutive patients that received an ICD during 1993-2002 at our institution for a median of 6.1 years. Information about heart disease, index arrhythmia, follow-up and death was extracted from medical records. RESULTS: The crude mortality was 26% (32/124). One- and two-year mortality was 6% and 12%, estimated 5- and 10-year mortality 20% and 33%. The cause of death was heart failure in 75% of deaths. The ejection fraction was below 35% in 91% of the 32 patients who died. We estimated that 28% of the patients received lifesaving therapy. The relative number of saved lives and complications was not related to the ejection fraction. CONCLUSION: Patients with preserved left ventricular function are excellent candidates for ICD, with life-saving ICD therapies in a substantial proportion, low mortality and good quality of life.

Reduction of fluoroscopy duration in radiofrequency ablation obtained by the use of a non-fluoroscopic catheter navigation system.

AIMS: Radiofrequency (RF) ablation requires placement of several catheters at critical positions. The catheters are positioned with fluoroscopy, resulting in a significant radiation exposure. We have investigated to what degree an intracardiac navigation system reduces the fluoroscopy duration in different groups of routine RF ablations. METHODS AND RESULTS: The fluoroscopy time was evaluated in 365 consecutive routine RF ablations, performed between 2002 and 2005. An intracardiac navigation system (LocaLisa, Medtronic) was used from 2003. The data were prospectively entered into a database and subsequently retrieved, and the procedures classified as being performed with fluoroscopy only or with the aid of the LocaLisa system. After introduction of the LocaLisa system, the median fluoroscopy time decreased from 24 to 10 min in the 141 atrioventricular nodal re-entry tachycardia (AVNRT) ablations and from 43 to 28 min in the 71 atrial flutter (AFl) ablations (P<0.005 for both). In the 145 Wolff-Parkinson-White (WPW) ablations, a decrease from 27 to 23 min was observed (P=0.03). The decrease in AVNRT and AFl, but not in WPW was associated with the introduction of the LocaLisa system. CONCLUSION: The use of the LocaLisa system during RF ablations significantly reduced the fluoroscopy time in AVNRT and AFl ablations, by a median of 58% and 46%, respectively.