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Alonso, C.,et al.: Clinical Testing of a New Pacemaker Function to Monitor Ventricular Capture. Automatic beat-by-beat capture functions are designed to minimize the pacing energy delivered, while maintaining the highest safety by delivering an immediate back-up stimulus in case of loss of capture. The objective of this study was to estimate the lowering of ventricular pacing amplitude allowed by such a function, compared to amplitudes usually set manually in routine practice. An automatic ventricular pacing threshold test is launched every 6 hours to measure the automatic capture threshold (AT). From AT the function calculates: (1) the“capture amplitude” (Vc)= AT+ 0.5 V at a minimum output of 1 V and (2) the“safety amplitude” (Vs)= twice AT at a minimum output of 2.5 V. The function preferentially uses Vc and verifies capture after each paced beat. In case of loss of capture, a back-up spike is delivered and Vs is implemented until the next threshold measurement. We estimated the ventricular amplitude delivered by the pacemaker from data stored in the pacemaker memory. We compared these values with the pacing amplitude typically programmed manually (MPA) by physicians at twice AT and a minimum of 2.5 V. Data from 57 recipients of Talent 3 DR pacemakers were analyzed. Complete data sets were available in 25 patients at 1 day, 28 at 1 month, and 39 between 1 day and 1 month. No loss of capture or ventricular pause was observed on 53 ambulatory electrocardiograms (ECG); and pulse amplitude automatically delivered by the device was significantly lower than the MPA at each of the three time points analyzed. This new beat-by-beat capture function allows a significant lowering of the pacing amplitude compared to manual settings, while preserving a 100% safety.(PACE 2005; 28:S39–S42) [ABSTRACT FROM AUTHOR]

Biventricular pacing has recently been proposed for treating patients with drug refractory heart failure and intraventricular conduction delay. The purpose is to restore ventricular relaxation and contraction sequences as homogeneously as possible. The aim of this study was to determine if some factors could predict the long-term clinical effectiveness of that new treatment. This study included 26 patients, aged 66 +/- 7 years, with drug refractory heart failure and wide QRS. Patients were implanted with a biventricular pacemaker. The left ventricle was paced through a coronary sinus tributary. New York Heart Association functional class, exercise tolerance, and left ventricular (LV) ejection fraction were collected at baseline and after pacemaker implantation. Patients were divided into 2 groups: group I = responders; group II = nonresponders. QRS duration and axis at baseline and during biventricular pacing, interventricular conduction time, and LV and right ventricular lead positions were compared between the 2 groups. Group I patients (n = 19) had a mean reduction of 1.3 in functional class and an increase in peak oxygen consumption rate by a mean of 50%. The only parameter that differed between the 2 groups was the QRS duration during biventricular pacing, with a significantly shorter value in group I than in group II (154 +/- 17 vs 177 +/- 26 ms; p = 0.016). Thus, a positive response to biventricular pacing is correlated with the quality of electrical resynchronization. The optimal positions of the right and LV leads would be those that could induce the greatest shortening of QRS duration. [ABSTRACT FROM AUTHOR]

Background: Since majority of sudden cardiac arrest (SCA) victims die in the intensive care unit (ICU), early etiologic investigations may improve understanding of SCA and targeted prevention.Methods: In this prospective, population-based registry all SCA admitted alive across the 48 hospitals of the Paris area were enrolled. We investigated the extent of early etiologic work-up among young SCD cases (<45 years) eventually dying within the ICU.Results: From May 2011 to May 2018, 4,314 SCA patients were admitted alive. Among them, 3,044 died in ICU, including 484 (15.9%) young patients. SCA etiology was established in 233 (48.1%) and remained unexplained in 251 (51.9%). Among unexplained (compared to explained) cases, coronary angiography (17.9 vs. 49.4%, P < 0.001), computed tomography scan (24.7 vs. 46.8%, P < 0.001) and trans-thoracic echocardiography (31.1 vs. 56.7%, P < 0.001) were less frequently performed. Only 22 (8.8%) patients with unexplained SCD underwent all three investigations. SCDs with unexplained status decreased significantly over the 7 years of the study period (from 62.9 to 35.2%, P = 0.005). While specialized TTE and CT scan performances have increased significantly, performance of early coronary angiography did not change. Autopsy, genetic analysis and family screening were performed in only 48 (9.9%), 5 (1.0%) and 14 cases (2.9%) respectively.Conclusions: More than half of young SCD dying in ICU remained etiologically unexplained; this was associated with a lack of early investigations. Improving early diagnosis may enhance both SCA understanding and prevention, including for relatives. Failure to identify familial conditions may result in other preventable deaths within these families. [ABSTRACT FROM AUTHOR]

Background: Procalcitonin (PCT) is increasingly being used for the diagnostic and prognostic work up of patients with suspected infections in the emergency department (ED). Recently, B∙R∙A∙H∙M∙S PCT direct, the first high s∙ensitive point-of-care test (POCT), has been developed for fast PCT measurement on capillary or venous blood samples. Methods: This is a prospective, international comparison study conducted in three European EDs. Consecutive patients with suspicion of bacterial infection were included. Duplicate determination of PCT was performed in capillary (fingertip) and venous whole blood (EDTA), and compared to the reference method. The diagnostic accuracy was evaluated by correlation and concordance analyses. Results: Three hundred and three patients were included over a 6-month period (60.4% male, median age 65.2 years). The correlation between capillary or venous whole blood and the reference method was excellent: r² = 0.96 and 0.97, sensitivity 88.1% and 93.0%, specificity 96.5% and 96.8%, concordance 93% and 95%, respectively at a 0.25 µg/L threshold. No significant bias was observed (-0.04 and -0.02 for capillary and venous whole blood) although there were 6.8% and 5.1% outliers, respectively. B∙R∙A∙H∙M∙S PCT direct had a shorter time to result as compared to the reference method (25 vs. 144 min, difference 119 min, 95% CI 110-134 min, p < 0.0001). Conclusions: This study found a high diagnostic accuracy and a faster time to result of B∙R∙A∙H∙M∙S PCT direct in the ED setting, allowing shortening time to therapy and a more wide-spread use of PCT. [ABSTRACT FROM AUTHOR]

Introduction This study aimed to evaluate the safety and efficacy of utilising an innovative radiofrequency (RF) powered flexible needle to achieve transseptal puncture (TSP). Methods and Results A RF powered flexible needle (Toronto catheter, Baylis Medical Company Inc.) associated with a stiffer dilator (Torflex Superstrong, Baylis Medical Company Inc.) was used in 125 consecutive patients referred for left sided ablations (mean age = 55.6, male = 86.5%) and compared with a standard transseptal set (BRK needle, SL0 sheath and dilator, St Jude Medical, Inc.) used in the previous 100 patients (mean age = 56, male 82%). TSP was achieved in 95/100 patients in the Brockenbrough group and in all 125 patients in the Toronto group (p=0.01) despite an equivalent proportion of difficult situations (8 and 9% respectively) and patients with a prior TSP (17% vs 24%). 7/100 needle related events (failure, aborted attempt or pericardial effusion) occurred in the Brockenbrough group and none in the Toronto group (p=0.01). The Toronto needle crossed the septum at the first attempt in 123/125 (98.4%) patients and the Brockenbrough needle in 84/95 (88%) patients (p<0.001). Conclusion Our data suggest that the Toronto RF powered flexible needle is safer and more efficient than a standard Brockenbrough needle and can be used not only in difficult situations but routinely to achieve TSP. [ABSTRACT FROM AUTHOR]

Abstract: The long-term relationship between cardiac arrhythmias and sleep apnoea in myotonic dystrophy (DM1) is unknown. Pacemakers enabling the long-term monitoring of electrocardiographic and ventilation parameters were implanted in 20 patients with DM1 (mean age=42±11.6 years), followed 40±12.3 months. Arrhythmias were recorded by the pacemaker in 17 patients (85%): 14 developed arrhythmic episodes that occurred either in absence or in presence of concomitant sleep apnoea. Conversely, among these 14 patients, the majority of sleep apnoea episodes were not associated with concomitant arrhythmias. In the other three patients who developed arrhythmias, simultaneous sleep apnoea was never observed. Episodes of sleep apnoea were observed in all patients, though only 85% presented with sleep apnoea syndrome. In conclusion, a high incidence of arrhythmias and sleep apnoea was observed. While arrhythmias are generally attributable to an organic substrate, they are sometimes precipitated by functional triggers, as in the case of sleep apnoea. [Copyright &y& Elsevier]

MORTENSEN, P.T., et al.: Sequential Biventricular Pacing: Evaluation of Safety and Efficacy. The study evaluated the clinical safety, performance, and efficacy of sequential biventricular pacing in the InSync III (Model 8042) biventricular stimulator in a multicenter, prospective 3-month study and assessed the proper functioning of features aiming at improving biventricular AV therapy delivery. The system was successfully implanted in 189 (95.9%) of 198 patients with symptomatic systolic heart failure and a prolonged QRS complex duration. Patients significantly improved their 6-minute hall walk distance (baseline 339 ± 92 vs 3-month 422 ± 127 meter, P < 0.001) and NYHA class (baseline 3.1 ± 0.5 vs 3-month 1.9 ± 0.7, P < 0.001). Echocardiographic optimization of sequential biventricular pacing showed an improvement in stroke volume compared to simultaneous stimulation (sequential 68 ± 24 mL vs simultaneous 56 ± 23 mL, P < 0.001) at baseline and at 3 months. In 88% (30/34) of the patients these improvements were seen within a small range of V-V delays of ±20 ms and in 94% (32/34) within V-V delays of ±40 ms. In contrast, programming beyond this range reduced stroke volume below that during simultaneous biventricular pacing. The device functioned as expected. LV lead dislodgement was observed in 12 patients and phrenic nerve stimulation required lead repositioning in 2 patients. Eight patients died during the study. Patient survival at 3 and 6 months was 97 ± 2% and 94 ± 2%, respectively. Cause of death was cardiac (n = 7), heart failure related (n = 3), arrhythmia related (n = 2), and unknown (n = 2). In conclusion, this sequential biventricular pacemaker was safe and efficacious. (PACE 2004; 27:339–345) [ABSTRACT FROM AUTHOR]

TOUSSAINT, J.-F., et al.: Basal Asynchrony and Resynchronization with Biventricular Pacing Predict Long-Term Improvement of LV Function in Heart Failure Patients. --> Biventricular pacing (BiV) is emerging for patients with dilated cardiomyopathy (DCM) and asynchrony. We measured basal asynchrony and early resynchronization by radionuclide angioscintigraphy (RNA) in order to predict long‐term evolution of ventricular function after BiV. Thirty‐four patients (NYHA Class III–IV,65.4 ± 11 years) with large QRS(179 ± 18 ms)were implanted with BiV and studied by RNA before (D0), at day 8 (D8), and during follow‐up(20 ± 7 months). We calculated left and right ejection fractions, the interventricular dyssynchrony (TRVLV), and the apicobasal dyssynchrony (Tab). LVEF improved from20.2 ± 8.1%(D0) to27.1%± 12.6%(follow‐up,P < 0.003vs D0) and RVEF from28.6%± 13%(D0) to34.3 ± 11.5%(follow‐up,P < 0.03vs D0). Inter‐ (ΔTRVLV) and intraventricular resynchronization was immediate and remained stable: TRVLV decreased from68.3 ± 38 ms(D0) to13.4 ± 48.5 ms(D8) and1.8 ± 39.2 ms(follow‐up,P < 0.0001vs D0); and Tab from45.8 ± 64.1 msto−18 ± 68(D8) and−28.3 ± 53.6 ms(follow‐up,P < 0.0001vs D0). Early inter‐ and intraventricular resynchronization (ΔTab) at D8 were related to late LVEF and RVEF improvement. Together, an LVEF > 15% and a significant interventricular dyssynchrony (TRVLV > 60 ms) at D0 have a sensitivity of 79% and a positive predictive value of 83% to predict an improvement of LVEF superior to 5% at follow‐up. In DCM patients, BiV resynchronizes ventricles early and in the long‐term, while RVEF and LVEF improve progressively. Patients with large electromechanical dyssynchrony benefit most from BiV. (PACE 2003; 26:1815–1823) [ABSTRACT FROM AUTHOR]

: ObjectivesThe main objective of this study was to assess if the benefits of biventricular (BiV) pacing observed during the crossover phase were sustained over 12 months.: BackgroundMUltisite STimulation In Cardiomyopathies (MUSTIC) is a randomized controlled study intended to evaluate the effects of BiV pacing in patients with New York Heart Association (NYHA) class III heart failure and intraventricular conduction delay.: MethodsOf 131 patients included, 42/67 in sinus rhythm (SR) and 33/64 in atrial fibrillation (AF) were followed up longitudinally at 9 and 12 months by 6-min walked distance, peak oxygen uptake (peak VO2), quality of life by the Minnesota score, NYHA class, echocardiography, and left ventricular ejection fraction by radionuclide technique.: ResultsAt 12 months, all SR and 88% of AF patients were programmed to BiV pacing. Compared with baseline, the 6-min walked distance increased by 20% (SR) (p = 0.0001) and 17% (AF) (p = 0.004); the peak VO2 by 11% (SR) and 9% (AF); quality of life improved by 36% (SR) (p = 0.0001) and 32% (AF) (p = 0.002); NYHA class improved by 25% (SR) (p = 0.0001) and 27% (AF) (p = 0.0001). The ejection fraction improved by 5% (SR) and 4% (AF). Mitral regurgitation decreased by 45% (SR) and 50% (AF).: ConclusionsThe clinical benefits of BiV pacing appeared to be significantly maintained over a 12-month follow-up period. [Copyright &y& Elsevier]