[Telemedicine for patients with cardiac implants : Insights into everyday practice of remote monitoring in Germany in 2022]. / Telemedizinische Versorgung von Patienten mit kardialen Implantaten : Einblick in die telekardiologische Versorgungsrealität in Deutschland im Jahr 2022.

BACKGROUND: As telemedical structures continues to be developed in the German healthcare system, remote monitoring is becoming increasingly important to ensure comprehensive, outpatient, and tailored care. The national quality assurance measure "DOQUVIDE-Documentation of quality in the assessment of vital parameters by implanted devices" is used to provide insight into everyday care for patients with telemedicine-enabled devices in Germany. METHODS: DOQUVIDE is a measuring instrument for recording outpatient remote monitoring for patients with implanted pacemaker, implantable cardioverter defibrillator (ICD), cardiac resynchronization therapy with a pacemaker (CRT-P), CRT defibrillator (CRT-D) devices and event recorder. DOQUVIDE records telemedically measured vital signs as well as cardiac events and the associated procedures initiated by cardiologists using standardized forms. RESULTS: In 74 practices/clinics in 14 federal states, 6687 patients received telemedical care in 2022; 937 were newly enrolled. These (60% male) were on average 77.8 years old, mainly with New York Heart Association (NYHA) class II (62.6%). A total of 5801 electronic records were generated as a result of telecardiology events, of which 3590 were due to pathological atrial fibrillation and 1812 due to ventricular high-frequency episodes. 295 events were triggered by event recorders and 95 by device therapies. The main measures taken were telephone contacts or outpatient visits. CONCLUSION: Remote monitoring has become a reality in German healthcare. Standardized processes and the establishment of quality assurance measures enable the definition of common quality standards and the identification of the potential for further development and simplify implementation in day-to-day care for practices.

The Use of a Quadripolar Left Ventricular Lead Increases Successful Implantation Rates in Patients with Phrenic Nerve Stimulation and/or High Pacing Thresholds Undergoing Cardiac Resynchronisation Therapy with Conventional Bipolar Leads.

BACKGROUND: Phrenic nerve stimulation (PNS) and high pacing thresholds (HPT) hinder biventricular stimulation in patients (pts) undergoing cardiac resynchronization therapy (CRT). A new quadripolar left ventricular (LV) lead (Quartet 1458Q, St. Jude Medical) with increased number of pacing configuration, might overcome this problem. METHODS: All consecutive pts in whom a standard bipolar lead intraoperatively resulted in PNS and/or HPT (≥4.00V/1mV), received, during the same implant, a quadripolar LV lead. Aim of the study was to evaluate acute and short term outcome. RESULTS: 26 pts [24 (92%) male, mean age 74±6 years)] with PNS (22 pts; 85%) and HPT (4 pts; 15%) were included. Permanent right ventricular pacing was the reason for broad QRS complex in 4 (15%) pts, whereas all other pts had a left bundle branch block. Severely symptomatic (NYHA Class ≥3) heart failure with reduced ejection fraction (EF 31±9%) was mostly caused by ischemic heart disease (14 pts; 54%). Idiopathic dilated cardiomyopathy and valvular heart disease were diagnosed in 6 (23%) pts each. In most (24/26, 92%) pts the use of the Quartet lead led to successful biventricular pacing due to a significant reduction in intraoperative pacing threshold (5.2V/1.0ms vs. 1.4V/0.8ms; p=0.03), which was maintained (1.2V/0.7ms) at follow-up. PNS never represented reason for failed LV pacing, neither acutely nor during follow-up. CONCLUSION: Excessively HPT and/or PNS are frequently encountered when conventional bipolar leads are used for CRT. A new quadripolar LV lead increases the rate of successful biventricular stimulation. Lower pacing threshold and freedom from PNS are maintained at follow-up.

Delayed rhythm control of atrial fibrillation may be a cause of failure to prevent recurrences: reasons for change to active antiarrhythmic treatment at the time of the first detected episode.

Atrial fibrillation (AF) is associated with impaired functional capacity and quality of life and significant morbidity and mortality. The current management approach fails to maintain stable sinus rhythm (SR) in the majority of patients. For many years, guidelines have recommended antiarrhythmic treatment of a first AF episode only if the AF is poorly tolerated, a position that has been reinforced by studies showing no mortality or morbidity advantage of rhythm control over rate control. During the last decade, research has shown mechanisms of self-perpetuation of AF based on electrophysiological and structural remodelling induced by AF itself. There is mounting evidence that 'lone' AF is because of a host of factors, some of which may be easily treatable, such as hypertension, sleep apnoea, and obesity, thus allowing secondary prevention at the time of the first episode of AF. According to these concepts, lack of early intervention could be one of the reasons for long-term failure of maintenance of SR. In this position paper, we propose testing the working hypothesis that if an SR maintenance strategy is selected, treatment of AF should commence at the first-detected episode and should be based on a double strategy of SR restoration and aggressive treatment of associated conditions that promote atrial remodelling.

Pilot study: Noninvasive monitoring of oral flecainide's effects on atrial electrophysiology during persistent human atrial fibrillation using the surface electrocardiogram.

BACKGROUND: The relation between flecainide's plasma level and its influence on human atrial electrophysiology during acute and maintenance therapy of atrial fibrillation (AF) is unknown. Therefore, this study determined flecainide plasma levels and atrial fibrillatory rate obtained from the surface ECG during initiation and early maintenance of oral flecainide in patients with persistent lone AF and assessed their relationship. METHODS AND RESULTS: In 10 patients (5 males, mean age 63 +/- 14 years, left atrial diameter 46 +/- 3 mm) with persistent lone AF, flecainide was administered as a single oral bolus (day 1) followed by 200-400 mg/day (days 2-5). The initial 300 mg flecainide bolus resulted in therapeutic plasma levels in all patients (range 288-629 ng/ml) with no side effects. Flecainide plasma levels increased on day 3 and remained stable thereafter. Day 5 plasma levels were lower (508 +/- 135 vs 974 +/- 276 ng/ml, P = 0.009) in patients with daily mean flecainide doses of 200 mg compared to patients with higher maintenance doses. Fibrillatory rate obtained from the surface electrocardiogram measuring 378 +/- 17 fpm at baseline was reduced to 270 +/- 18 fpm (P < 0.001) after the flecainide bolus but remained stable thereafter. Fibrillatory rate reduction was independent of flecainide plasma levels or clinical variables. CONCLUSION: A 300 mg oral flecainide bolus is associated with electrophysiologic effects that are not increased during early maintenance therapy in persistent human lone AF. In contrast to drug plasma levels, serial analysis of fibrillatory rate allows monitoring of individual drug effects on atrial electrophysiology.

Time-frequency analysis of the surface electrocardiogram for monitoring antiarrhythmic drug effects in atrial fibrillation.

This study explored time-frequency analysis of surface electrocardiograms in patients with persistent atrial fibrillation for monitoring atrial drug action. Drug loading over 3 days with oral flecainide (n = 13) or amiodarone (n = 17) organized the fibrillatory process expressed by decreased atrial fibrillatory rate, increased rate stability, and decreased exponential decay. Effects were more pronounced with flecainide than with amiodarone.

Characterization of left ventricular activation in patients with heart failure and left bundle-branch block.

BACKGROUND: Conventional activation mapping in the dilated human left ventricle (LV) with left bundle-branch block (LBBB) morphology is incomplete given the limited number of recording sites that may be collected in a reasonable time and given the lack of precision in marking specific anatomic locations. METHODS AND RESULTS: We studied LV activation sequences in 24 patients with heart failure and LBBB QRS morphology with simultaneous application of 3D contact and noncontact mapping during intrinsic rhythm and asynchronous pacing. Approximately one third of the patients with typical LBBB QRS morphology had normal transseptal activation time and a slightly prolonged or near-normal LV endocardial activation time. A "U-shaped" activation wave front was present in 23 patients because of a line of block that was located anteriorly (n=12), laterally (n=8), and inferiorly (n=3). Patients with a lateral line of block had significantly shorter QRS (P<0.003) and transseptal durations (P<0.001) and a longer distance from the LV breakthrough site to line of block (P<0.03). Functional behavior of the line of block was demonstrated by a change in its location during asynchronous ventricular pacing at different sites and cycle lengths. CONCLUSIONS: A U-shaped conduction pattern is imposed on the LV activation sequence by a transmural functional line of block located between the LV septum and the lateral wall with a prolonged activation time. Assessment of functional block is facilitated by noncontact mapping, which may be useful for identifying and targeting specific locations that are optimal for successful cardiac resynchronization therapy.

Safety and efficacy of enoxaparin compared with unfractionated heparin and oral anticoagulants for prevention of thromboembolic complications in cardioversion of nonvalvular atrial fibrillation: the Anticoagulation in Cardioversion using Enoxaparin (ACE) trial.

BACKGROUND: Anticoagulation in cardioversion of atrial fibrillation is currently performed with unfractionated heparin (UFH) and oral anticoagulants, with or without guidance by transesophageal echocardiography (TEE). Low-molecular-weight heparins may reduce the risk of bleeding, may obviate the need for intravenous access, and do not require frequent anticoagulation monitoring. METHODS AND RESULTS: In a randomized, prospective multicenter trial, we compared the safety and efficacy of enoxaparin administered subcutaneously with intravenous UFH followed by the oral anticoagulant phenprocoumon in 496 patients scheduled for cardioversion of atrial fibrillation of >48 hours' and < or =1 year's duration. Patients were stratified to cardioversion with (n=431) and without (n=65) guidance by TEE. The study aimed to demonstrate noninferiority of enoxaparin compared with UFH+phenprocoumon with regard to the incidence of embolic events, all-cause death, and major bleeding complications. Secondary end points included successful cardioversion, maintenance of sinus rhythm until study end, and minor bleeding complications. Of 496 randomized patients, 428 were analyzed per protocol. Enoxaparin was noninferior to UFH+phenprocoumon with regard to the incidence of the composite primary end point in a per-protocol analysis (7 of 216 patients versus 12 of 212 patients, respectively; P=0.016) and in an intention-to-treat analysis (7 of 248 patients versus 12 of 248 patients, respectively; P=0.013). There was no significant difference between the 2 groups in the number of patients reverted to sinus rhythm. CONCLUSIONS: Enoxaparin is noninferior to UFH+phenprocoumon for prevention of ischemic and embolic events, bleeding complications, and death in TEE-guided cardioversion of atrial fibrillation. Its easier application and more stable anticoagulation may make it the preferred drug for initiation of anticoagulation in this setting.

Use of subcutaneous enoxaparin compared to intravenous heparin and oral phenprocoumon in the setting of cardioversion--the ACE study (Anticoagulation in Cardioversion using Enoxaparin).

The mode and duration of anticoagulation in the setting of cardioversion of atrial fibrillation-either with or without guidance by transesophageal echocardiography (TEE)-is still an unresolved issue. Oral anticoagulation with warfarin or phenprocoumon is frequently used but may be associated with an increased risk of bleeding complications or, conversely, episodes of undercoagulation. Moreover, it takes several days to reach full anticoagulation with oral compounds. This phase may be covered with intravenous heparin but this requires prolonged hospitalization. Low-molecular weight heparin is an attractive alternative as it not only provides a safe and predictable level of anticoagulation with few side effects but can also be administered safely on an outpatient basis. In addition, anticoagulation monitoring is usually unnecessary. The ACE study (Anticoagulation in Cardioversion using Enoxaparin) compared the safety and efficacy of subcutaneous enoxaparin with intravenous heparin/oral phenprocoumon before and after cardioversion (stratified to TEE guidance or no TEE guidance). This article summarizes the study rationale and design. The results will be published shortly.

Echocardiographic and electrocardiographic predictors for atrial fibrillation recurrence following cardioversion.

INTRODUCTION: Identification of suitable candidates for cardioversion currently is not based on individual electrical and mechanical atrial remodeling. Therefore, this study analyzed the meaning of atrial fibrillatory rate obtained from the surface ECG (as a measure of electrical remodeling) and left atrial size (as measure of mechanical remodeling) for prediction of early atrial fibrillation (AF) recurrence following cardioversion. METHODS AND RESULTS: Forty-four consecutive patients (26 men and 18 women, mean age 62 +/- 11 years, no antiarrhythmic medication at baseline) with persistent AF were studied. Fibrillatory rate was obtained from high-gain, high-resolution surface ECG using digital signal processing (filtering, QRST subtraction, Fourier analysis) before electrical cardioversion. Univariate and multivariate regression analysis revealed larger systolic left atrial area (Beta = 0.176, P = 0.031) obtained by precardioversion echocardiogram from the apical four-chamber view and higher atrial fibrillatory rate (Beta = 0.029, P = 0.021) to be independent predictors for AF recurrence (n = 13). Stratification based on the regression equation (electromechanical index [EMI] = 0.176 systolic left atrial area + 0.029 fibrillatory rate - 17.674) allowed identification of groups at low, intermediate, or high risk. No patient with an EMI < -1.85 had early AF recurrence, as opposed to 78% with an EMI > -0.25. Intermediate results (40% recurrence rate) were obtained when the calculated EMI ranged between -1.85 and -0.25 (P < 0.001). CONCLUSION: Fibrillatory rate obtained from the surface ECG and systolic left atrial area obtained by echocardiography may predict early AF recurrence in patients with persistent AF. These parameters might be useful in identifying candidates with a high likelihood of remaining in sinus rhythm after cardioversion.