Findings of an observational investigation of pure remote follow-up of pacemaker patients: is the in-clinic device check still needed?

BACKGROUND: Device follow-up is mandatory in the care of patients with a pacemaker. However, in most cases, device checks appear to be mere technical, time-consuming procedures. The aim of this research is to evaluate whether remote follow-up can replace in-clinic device checks by assessing clinical outcomes for pacemaker patients followed only via remote follow-up. METHODS AND RESULTS: Consecutive pacemaker patients followed with remote monitoring were prospectively included by 6 Italian cardiology centers in an observational investigation. The workflow for remote monitoring included an initial assessment by nursing staff and, when necessary, by a responsible physician for medical decisions. No in-person visits were scheduled after the start of remote monitoring. One-thousand and two-hundred and fifty one patients (30% female, 75±11years old) were followed for a median observation period of 15months. Out of 4965 remote transmissions, 1882 (38%) had at least one clinically relevant event to be investigated further, but, only after 137 transmissions (2.8%), the patients were contacted for an in-clinic visit or hospitalization. Sixty-nine patients died and 124 were hospitalized for various reasons. Atrial fibrillation episodes were the most common clinical events discovered by remote transmissions, occurring in 1339 (26%) transmissions and 471 (38%) patients. CONCLUSIONS: Our experience shows that remote monitoring in a pacemaker population can safely replace in-clinic follow-up, avoiding unnecessary in-hospital device follow-up.

Predictors of left atrium appendage clot detection despite on-target warfarin prevention for atrial fibrillation.

BACKGROUND AND PURPOSE: The antithrombotic management of atrial fibrillation (AF) is currently based on clinical scores (CHADS(2) or CHA(2)DS(2)VASc). The prevalence of left atrium (LA) thrombi in effectively anticoagulated AF patients has been reported as being up to 7.7 %. We tried to correlate LA/LA appendage (LAA) thrombus detection with possible clinical predictors in warfarin-treated patients. METHODS: We performed trans-esophageal echocardiography on 430 patients (mean age, 60.3 ± 9.8 years) receiving oral anticoagulant (OAC) therapy and undergoing pulmonary vein isolation. In 10/430 (2.3 %), an LA thrombus was found despite therapeutic OAC (mean INR 2.6 ± 0.6; range, 2.0-3.8) over the previous 4 weeks. RESULTS: Two study groups were identified: 1. T-positive group = with LAA thrombus (10 patients) 2. T-negative group = without LAA thrombus (420 patients) The T-positive patients had a higher CHADS(2) score (1.5 ± 0.7 versus 0.7 ± 0.8; p = 0.004), a lower LVEF (54.7 ± 9.5 % versus 60.2 ± 7.4; p = 0.02), and a larger LA size (LA diameter, 56 ± 12.2 mm versus 46 ± 6.5 mm; p < 0.001and normalized LA volume: 140.2 ± 66 ml/m² vs. 67 ± 39 ml/m²; p < 0.05). On multivariate analysis, a larger LA diameter and normalized LA volume (OR, 1.14; 95 % C.I., 1.04-1.26; p = 0.006 and OR, 1.02; 95 % C.I., 1.01-1.03; p = 0.001, respectively) and a higher CHA(2)DS(2)VASc score (OR, 2.4; 95 % C.I., 1.4-4.2; p = 0.001) predicted left atrium appendage (LAA) thrombus. In another 42/430 (9.8 %) patients, an LA spontaneous echo-contrast (SEC) was detected. Thus, cumulatively, 52/430 (12.1 %) patients had either LAA thrombi (10 patients) or SEC (42 patients). LA diameter continued to predict the presence of either thrombi or SEC (OR, 1.14; 95 % C.I., 1.07-1.2; p < 0.05). CONCLUSIONS: We found a 2.3 % prevalence of LA thrombus (12.1 % when SEC was also considered). The thrombus was present despite on-target warfarin prevention. In addition to a higher CHA(2)DS(2)VASc score, a larger LA size was a strong predictor of clot detection.

Activation mapping to determine the mechanism of atrial tachycardia when pacing techniques are not feasible.

AIM: Atrial tachycardia/flutter (ATAF) could be sustained by a focus or a reentry circuit, which mapping differs significantly. Entrainment mapping is widely used to detect reentry, but it is not always feasible. We evaluated an activation mapping protocol to differentiate macro, micro-reentrant and focal ATAFs. METHODS: Among 454 patients who underwent ablation for supraventricular tachycardia (SVT) between December, 2004 and August, 2008, 52 ATAF patients were selected and assessed by means of activation mapping (study mapping protocol). The remaining 402 cases (AVNRT, AVRT, and common atrial flutter) were excluded. RESULTS: Fifty-eight ATAF morphologies were mapped (mean CL 297.2±98 ms). The protocol identified the ATAF mechanism in 53/58 (91%, 52 successfully ablated) morphologies, while the mapping technique failed in 5/58 (9%) cases/patients. Among the 53 ATAF diagnoses, 25/53 (47%) were macroreentrant ATAFs (MATs), whereas 12/53 (23%) were focal ATAFs (FATs) or microreentrant ATAFs (MIATs) (16/53, 30%). Ablation was successful in 25/25 cases of the MAT group, in 11/12 (91.7%) cases of the FAT group, and in 16/16 cases of the MIAT group. At the end of the procedure, no ATAF was inducible in 44/52 (85%) patients. The study protocol was successfully validated in 20 patients (10 with AVNRT, and 10 with common atrial flutter) of the control group. After a mean follow-up of 21.5±12.5 months, 36/52 (70%) pts resulted free from ATAF. Non-inducibility predicted long-term freedom from ATAF (92.1 % vs. 60 %, P=0.005, OR 0.09; 95% CI 0.18-0.51, P=0.006). CONCLUSION: Activation mapping alone may be reliable to determine the ATAF mechanism, especially when pacing techniques are not feasible.

Long term follow up of radiofrequency catheter ablation of atrial flutter: clinical course and predictors of atrial fibrillation occurrence.

OBJECTIVES: To evaluate the time to onset and the predictors of atrial fibrillation (AF) during long term follow up of patients with typical atrial flutter (AFL) treated with transisthmic ablation. DESIGN: Prospective multicentre study. METHODS AND RESULTS: 383 patients (75.4% men, mean (SD) age 61.7 (11.1) years) who underwent transisthmic ablation for typical AFL were investigated. In 239 patients (62.4%) AF was present before ablation. Ablation proved successful in 367 patients (95.8%). During a mean (SD) follow up of 20.5 (12.4) months, 41.5% of patients reported AF. The cumulative probability of postablation AF increased continuously as time passed: it was 22% at six months, 36% at one year, 50% at two years, 58% at three years, and 63% at four years. CONCLUSIONS: AF occurred in a large proportion of patients after transisthmic catheter ablation of typical AFL. The occurrence of AF was progressive during follow up. Preablation AF, age < 65 years, and left atrial size > 50 mm are associated with postablation AF occurrence.

Success of serial external electrical cardioversion of persistent atrial fibrillation in maintaining sinus rhythm; a randomized study.

AIMS: The aim of this prospective, randomized study was to determine the efficacy of a serial external electrical cardioversion strategy in maintaining sinus rhythm after 12 months in patients with recurrent persistent atrial fibrillation. METHODS AND RESULTS: Ninety patients with persistent atrial fibrillation lasting more than 72 h but less than 1 year were randomized in a one to one fashion to repetition of up to two electrical cardioversions in the event of relapse of atrial fibrillation detected within 1 month of the previous electrical cardioversion (Group AGG), or to non-treatment of atrial fibrillation relapse (Group CTL). ECGs were scheduled at 6 h, 7 days, and 1 month. Clinical examination and ECGs were repeated during the 6-month and 12-month follow-up examinations. Echocardiography was repeated during the 6-month follow-up examination. Clinical and echocardiographic characteristics were similar in the two groups. All patients were treated with antiarrhythmic drugs before electrical cardioversion and throughout follow-up. After 12 months, sinus rhythm was maintained in 53% of Group AGG patients and in 29% of Group CTL patients (P<0.03). After 6 months, left ventricular ejection fraction had recovered significantly only in Group AGG (56.8 +/- 9.0% at enrollment vs 60.4 +/- 9.4% at 6 months,P <0.001). CONCLUSION: These results demonstrate that an aggressive policy towards persistent atrial fibrillation by means of repetition of electrical cardioversion after early atrial fibrillation recurrence is useful in maintaining sinus rhythm after 12 months.

[Coronary angiography in two defined populations: Padua and Citadella]. / La coronarografia in due popolazioni definite: a Padova ed a Cittadella.

BACKGROUND: Coronary angiography is an invasive procedure that is relatively expensive and that requires an appropriate indication. METHODS: Utilization rate and the appropriateness of the use of the coronary angiography have been compared in two defined populations, namely residents from the city of Padua (group A), and subjects from the local health unit of Cittadella (group B), who underwent coronary angiography between June 1, 1992 and May 31, 1993. Appropriateness was evaluated both by comparison with the AHA/ACC guidelines and by observation of the outcome following diagnosis one year after the coronary angiogram was performed. RESULTS: One hundred and seventy-one patients in group A and 100 patients in group B underwent coronary angiography: both groups had similar age and sex distribution. Utilization rate was 8 per 10,000 inhabitants in group A, and 10 per 10,000 inhabitants in group B. Appropriate coronary angiography, evaluated by comparison with the AHA/ACC guidelines, was 69.9% in group A and 68% in group B. Coronary angiogram showed at least one stenosis > or = 50% in 133 patients from group A and in 66 patients from group B. These patients were followed up for at least 12 months. Of 13 deaths, 12 occurred as fatal cardiac events, while of the 147 surviving patients who had complete follow-up data, 114 (77%) improved. The outcome was measured through symptoms and stress test. In addition, subjective improvement was measured in group A using the "Nottingham Health Profile". CONCLUSIONS: Criteria of appropriateness for an invasive diagnostic procedure such as coronary angiography, which is a determinant "entry point" for revascularization procedures, is based on common clinical knowledge that may be evolving with time. Based on these data, it seems that the current guidelines could be modified, especially for indications within the setting of myocardial infarction.