Introduction: Permanent deep septal stimulation with capture of the left bundle branch (LBB) enables maintenance/restoration of the physiological activation of the left ventricle. However, it is almost always accompanied by the simultaneous engagement of the local septal myocardium, resulting in a fused (nonselective) QRS complex, therefore, confirmation of LBB capture remains difficult. Methods: We hypothesized that programmed extrastimulus technique can differentiate nonselective LBB capture from myocardial-only capture as the effective refractory period (ERP) of the myocardium is different from the ERP of the LBB. Consecutive patients undergoing pacemaker implantation underwent programmed stimulation delivered from the lead implanted in a deep septal position. Responses to programmed stimulation were categorized on the basis of sudden change in the QRS morphology of the extrastimuli, observed when ERP of LBB or myocardium was encroached upon, as: "myocardial," "selective LBB," or nondiagnostic (unequivocal change of QRS morphology). Results: Programmed deep septal stimulation was performed 269 times in 143 patients; in every patient with the use of a basic drive train of 600 milliseconds and in 126 patients also during intrinsic rhythm. The average septal-myocardial refractory period was shorter than the LBB refractory period: 263.0 ± 34.4 vs 318.0 ± 37.4 milliseconds. Responses diagnostic for LBB capture ("myocardial" or "selective LBB") were observed in 114 (79.7%) of patients.Conclusions: A novel maneuver for the confirmation of LBB capture during deep septal stimulation was developed and found to enable definitive diagnosis by visualization of both components of the paced QRS complex: selective paced LBB QRS and myocardial-only paced QRS. K E Y W O R D S effective refractory period, electrocardiogram, left bundle branch pacing, nonselective capture, refractoriness
Background: The highest priority in preventive cardiology is given to patients with established coronary artery disease (CAD). The aim of the study was to assess the current implementation of the guidelines for secondary prevention in everyday clinical practice by evaluating control of the main risk factors and the cardioprotective medication prescription rates in patients following hospitalization for CAD. Methods: Fourteen departments of cardiology participated in the study. Patients (aged ≤ 80 years) hospitalized due an acute coronary syndrome or for a myocardial revascularization procedure were recruited and interviewed 6-18 months after the hospitalization. Results: Overall, 947 patients were examined 6-18 months after hospitalization. The proportion of patients with high blood pressure (≥ 140/90 mmHg) was 42%, with high low-density lipoprotein cholesterol (LDL-C ≥ 1.8 mmol/L) 62%, and with high fasting glucose (≥ 7.0 mmol/L) 22%, 17% of participants were smokers and 42% were obese. The proportion of patients taking an antiplatelet agent 6-18 months after hospitalization was 93%, beta-blocker 89%, angiotensin converting enzyme inhibitor or sartan 86%, and a lipid-lowering drug 90%. Only 2.3% patients had controlled all the five main risk factors well (non-smoking, blood pressure < 140/90 mmHg, LDL-C < 1.8 mmol/L and glucose < 7.0 mmol/L, body mass index < 25 kg/m 2), while 17.9% had 1 out of 5, 40.9% had 2 out of 5, and 29% had 3 out of 5 risk factors uncontrolled. Conclusions: The documented multicenter survey provides evidence that there is considerable potential for further reductions of cardiovascular risk in CAD patients in Poland. A revision of the state funded cardiac prevention programs seems rational.
Dysglycemia, in this survey defined as impaired glucose tolerance (IGT) or type 2 diabetes, is common in patients with coronary artery disease (CAD) and associated with an unfavorable prognosis. This European survey investigated dysglycemia screening and risk factor management of patients with CAD in relation to standards of European guidelines for cardiovascular subjects. RESEARCH DESIGN AND METHODS The European Society of Cardiology's European Observational Research Programme (ESC EORP) European Action on Secondary and Primary Prevention by Intervention to Reduce Events (EUROASPIRE) V (2016-2017) included 8,261 CAD patients, aged 18-80 years, from 27 countries. If the glycemic state was unknown, patients underwent an oral glucose tolerance test (OGTT) and measurement of glycated hemoglobin A 1c. Lifestyle, risk factors, and pharmacological management were investigated. RESULTS A total of 2,452 patients (29.7%) had known diabetes. OGTT was performed in 4,440 patients with unknown glycemic state, of whom 41.1% were dysglycemic. Without the OGTT, 30% of patients with type 2 diabetes and 70% of those with IGT would not have been detected. The presence of dysglycemia almost doubled from that selfreported to the true proportion after screening. Only approximately one-third of all coronary patients had completely normal glucose metabolism. Of patients with known diabetes, 31% had been advised to attend a diabetes clinic, and only 24% attended. Only 58% of dysglycemic patients were prescribed all cardioprotective drugs, and use of sodium-glucose cotransporter 2 inhibitors (3%) or glucagon-like peptide 1 receptor agonists (1%) was small. CONCLUSIONS Urgent action is required for both screening and management of patients with CAD and dysglycemia, in the expectation of a substantial reduction in risk of further cardiovascular events and in complications of diabetes, as well as longer life expectancy.
Pulsatile blood pressure (BP) confers cardiovascular risk. Whether associations of cardiovascular end points are tighter for central systolic BP (cSBP) than peripheral systolic BP (pSBP) or central pulse pressure (cPP) than peripheral pulse pressure (pPP) is uncertain. Among 5608 participants (54.1% women; mean age, 54.2 years) enrolled in nine studies, median follow-up was 4.1 years. cSBP and cPP, estimated tonometrically from the radial waveform, averaged 123.7 and 42.5 mm Hg, and pSBP and pPP 134.1 and 53.9 mm Hg. The primary composite cardiovascular end point occurred in 255 participants (4.5%). Across fourths of the cPP distribution, rates increased exponentially (4.1, 5.0, 7.3, and 22.0 per 1000 person-years) with comparable estimates for cSBP, pSBP, and pPP. The multivariable-adjusted hazard ratios, expressing the risk per 1-SD increment in BP, were 1.50 (95% CI, 1.33–1.70) for cSBP, 1.36 (95% CI, 1.19–1.54) for cPP, 1.49 (95% CI, 1.33–1.67) for pSBP, and 1.34 (95% CI, 1.19–1.51) for pPP ( P <0.001). Further adjustment of cSBP and cPP, respectively, for pSBP and pPP, and vice versa, removed the significance of all hazard ratios. Adding cSBP, cPP, pSBP, pPP to a base model including covariables increased the model fit ( P <0.001) with generalized R 2 increments ranging from 0.37% to 0.74% but adding a second BP to a model including already one did not. Analyses of the secondary end points, including total mortality (204 deaths), coronary end points (109) and strokes (89), and various sensitivity analyses produced consistent results. In conclusion, associations of the primary and secondary end points with SBP and pulse pressure were not stronger if BP was measured centrally compared with peripherally.
Aims The recently introduced technique of direct transseptal pacing of the left bundle branch is poorly characterized with many questions with regard to the optimal implantation strategy and safety concerns largely left unanswered. We developed a cadaver model for deep septal lead deployment in order to investigate the depth of penetration in relation to lead behaviour, lead tip position, and the number of rotations. Methods and results Five fresh human hearts and five lumenless, 4.1-Fr pacing leads were used for deep septal deployment simulations. The leads were positioned with the use of a dedicated delivery sheath and screwed into the interventricular septum at several sites progressively more distal from the atrioventricular ring with a predetermined number of lead rotations. During each lead deployment, the depth of tip penetration was measured and the lead behaviour was noted. Four distinct lead behaviours were observed: (i) helix only penetration, no matter how many rotations were performed, due to the ‘endocardial entanglement effect’ (43.1% cases) or (ii) ‘endocardial barrier effect’ (19.6% cases), (iii) shallow/moderate penetration, with ensuing ‘drill effect’ when more rotations were added (9.8% cases), and (iv) deep progressive penetration with each additional rotation, occurring when the ‘screwdriver effect’ was present (27.4% cases, including three septal perforations). These different lead behaviours seemed to be determined by the lead position—mainly the strength of the initial endocardial layer—and the number of fully transmitted rotations. Conclusion New insights into deep septal lead deployment technique were gained with regard to safe and successful implantation.
Background: During permanent nonselective His bundle (ns-HB) pacing, it is crucial to confirm HB capture/exclude that only right ventricle (RV) myocardial septal pacing is present. Because the effective refractory period (ERP) of the working myocardium is different than the ERP of the HB, we hypothesized that it should be possible to differentiate ns-HB capture from RV myocardial capture using programmed extrastimulus technique. Methods: In consecutive patients during HB pacemaker implantation, programmed HB pacing was delivered from the screwed-in HB pacing lead. Premature beats were introduced at 10-ms steps during intrinsic rhythm and also after a drive train of 600 ms. The longest coupling interval that resulted in an abrupt change of QRS morphology was considered equal to ERP of HB or RV myocardium. Results: Programmed HB pacing was performed from 50 different sites in 32 patients. In 34 of 36 cases of ns-HB pacing, the RV myocardial ERP was shorter than HB ERP (271.8±38 versus 353.0±30 ms; P <0.0001). Programmed HB pacing using a drive train resulted in a typical abrupt change of paced QRS morphology: from ns-HB to RV myocardial QRS (34 of 36 cases) or to selective HB QRS (2 of 36 cases). Programmed HB pacing delivered during native conduction resulted in obtaining selective HB QRS in 20 of 34 and RV myocardial QRS in 14 of 34 of the ns-HB cases. In RV myocardial–only pacing cases (false ns-HB pacing, n=14), such responses were not observed—the QRS morphology remained stable. Therefore, the programmed HB pacing correctly diagnosed all ns-HB cases and all RV myocardial pacing cases. Conclusions: A novel maneuver for the diagnosis of HB capture, based on the differences in ERP between HB and myocardium, was formulated, assessed, and found as diagnostically valuable. This method is unique in enabling to visualize selective HB QRS in patients with otherwise obligatory ns-HB pacing (RV myocardial capture threshold <HB capture threshold).
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