Aim While sympathetic overactivity in heart failure (HF) with reduced ejection fraction (HFrEF; EF < 40%) is welldocumented, it is ill-defined in patients with mildly reduced EF (HFmrEF; EF 40-49%). Furthermore, the significance of ischaemic versus non-ischaemic aetiology in sympathetic activation is also unclear and has yet to be studied in HF. Our goal was to compare muscle sympathetic nerve activity (MSNA) in HFmrEF and HFrEF patients and in healthy subjects, as well as to elucidate the influence of the underlying disease. Methods and results Twenty-three HFrEF (age 58 ± 10 years), 33 HFmrEF patients (age 61 ± 10 years), including 11 subjects with non-ischaemic cardiomyopathy in each HF groups and 10 healthy controls (age 55 ± 10 years), were studied. MSNAdetected by peroneal microneurography, continuous arterial pressure, and ECG-was recorded. MSNA frequency (burst/min) and incidence (burst/100 cycles) were calculated. Association with the patients' characteristics were assessed, and aetiology-based comparisons were performed. Burst frequency demonstrated a significant stepwise increase in both HFmrEF (41 ± 11 burst/min) and HFrEF (58 ± 17 burst/min, P < 0.001) patients as compared with controls (27 ± 9; P < 0.001 for both HF groups). Similarly, burst incidences were 66 ± 17, 82 ± 15, and 36 ± 10 burst/100 cycles in HFmrEF, HFrEF patients, and in healthy controls, respectively (P < 0.001 for all). Burst frequencies in HF patients showed significant correlation with NT-proBNP levels, and significant inverse correlations with the subjects' mean RR intervals, stroke volumes, pulse pressures, and EF. Conclusions Muscle sympathetic nerve activity parameters indicated significant sympathetic activation in both HFmrEF and HFrEF patients as compared with healthy controls with no difference in relation to ischaemic versus non-ischaemic aetiology.
Background Anatomical characteristics of the left atrium and the pulmonary veins (PVs) may be relevant to the success rate of cryoballoon (CB)-ablation for atrial fibrillation (AF). Cardiac computed tomography (CCT) is considered as the gold standard for preablation imaging. Recently, three-dimensional transesophageal echocardiography (3DTOE) has been proposed for preprocedural assessment of cardiac structures relevant to CB-ablation. The accuracy of 3DTOE has not been validated by other imaging modalities. Objective We prospectively evaluated the feasibility and the accuracy of 3DTOE imaging for the assessment of left atrial and PV structures prior to pulmonary vein isolation (PVI). In addition, CCT was used to validate the measurements obtained with 3DTOE. Methods PV anatomy of 67 patients (59.7% men, mean age 58.5 ± 10.5 years) was assessed using both 3DTOE and CCT scan prior to PVI with the Arctic Front CB. The following parameters were measured bilaterally: PV ostium area (OA), the major and minor axis diameters of the ostium (a > b) and the width of the carina between the superior and the inferior PVs. In addition, the width of the left lateral ridge (LLR) between the left atrial appendage and the left superior PV. Evaluation of inter-technique agreement was based on linear regression with Pearson correlation coefficient (PCC) and Bland–Altman analysis of biases and limits of agreement. Results Moderate positive correlation (PCC 0.5–0.7) was demonstrated between the two imaging methods for the right superior PV’s OA and both axis diameters, the width of the LLR and left superior PV (LSPV) minor axis diameter (b) with limits of agreement ˂50% and no significant biases. Low positive or negligible correlation (PCC < 0.5) was found for both inferior PV parameters. Conclusions Detailed assessment of the right superior PV parameters, LLR and LSPV b is feasible with 3DTOE prior to AF ablation. This 3DTOE measurements demonstrated a clinically acceptable inter-technique agreement with those obtained with CCT. Graphical Abstract
Összefoglaló. Bevezetés: Az artériás baroreflex-érzékenységi (BRS-) indexek egységnyi nyomásváltozásra adott élettani válaszokat írnak le. Az RR-intervallum gyors válaszait a cardiovagalis BRS-indexekkel, a vasomotorválaszokat az izom szimpatikus idegi aktivitás (MSNA) válaszain alapuló szimpatikus-BRS-indexekkel jellemezzük. Szívelégtelenségben kórosan csökkent értékeik kedvezőtlen kimenetelt jeleznek. Betegek és módszerek: A BRS-indexek meghatározhatóságát 52, szívelégtelenségben szenvedő betegben (kor: 59 ± 10 év; EF: 37 ± 11%) és 11, kor szerint illesztett egészséges önkéntesben vizsgáltuk. EKG- és vérnyomásfelvételekből három cardiovagalis BRS-indexet számítottunk; a növekvő, illetve csökkenő spontán szekvenciák módszerén alapuló up-BRS-t és down-BRS-t, továbbá az alacsony frekvenciatartomány-beli ’cross-spectralis ’ indexet, az LF-alfát. Egy perifériás ideg (nervus peroneus) perkután punkciójával detektáltuk az MSNA szimpatikus csúcs incidenciáját (csúcs/100 szívciklus), s ezt korreláltattuk a diastolés nyomás 3 Hgmm sávokba rendezett értékeivel. Így nyertük a szimpatikus BRS jellemzőit, a BRSSY-incidencia-értékeket. Eredmények: Az up- és down-BRS-szekvenciák csak a betegek 19%-ában voltak meghatározhatók, az LF-alfa a 69%-ukban. Azok, akiknél cardiovagalis BRS nem volt meghatározható, szignifikánsan csökkent RR-intervallum-ingadozást és magasabb NT-proBNP-értékeket mutattak. A meghatározható cardiovagalis BRS-indexek nem különítették el a betegeket és a kontrollszemélyeket. A BRSSY-incidencia-érték 58%-ban állt rendelkezésre, s csakúgy, mint maga a „csúcs” incidencia, jól elkülönítette a betegeket és az önkénteseket. A hiányzó baroreflexérték a magas „csúcs” incidenciával állt összefüggésben. Következtetés: A cardiovagalis BRS-értékek csak korlátozottan alkalmasak egészséges önkéntesek és szívelégtelen betegek elkülönítésére, a meghatározhatatlan értékek súlyosabb betegségre utalnak. A BRSSY-incidencia elkülöníti az egészséges és a beteg csoportokat; a hiányzó érték a fokozott szimpatikus aktivitással áll összefüggésben. Orv Hetil. 2021; 162(3): 91–98. Summary. Introduction: Arterial baroreflex sensitivity (BRS) is characterized by the magnitude of physiological responses to arterial pressure changes. Rapid RR interval responses are quantified by cardiovagal BRS parameters, sympathetic responses could be assessed by changes in muscle sympathetic nerve activity (MSNA). Abnormal indices in heart failure are associated with poor outcome. Patients and methods: 52, heart failure patients (age 59 ± 10 years, EF 37 ± 11%), and 11, age-matched healthy volunteers were studied. From ECG and arterial pressure recordings up-BRS and down-BRS values were determined using the method of spontaneous sequences. The low frequency cross-spectral gain, the LF alpha was also determined. Percutaneous puncture of the peroneal nerves allowed determination of MSNA burst incidence (burst/100 cycles), which was correlated to corresponding diastolic pressure bins of 3 mmHg, yielding a sympathetic BRS, the BRSSY-incidence. Results: Up- and down-BRS could be calculated in 19% of the patients, LF alpha was determined in 69%. Those with missing cardiovagal BRS values showed diminished RR interval variation, and higher levels of NT-proBNP. The measurable cardiovagal BRS indices did not separate patients and healthy volunteers. BRSSY-incidence could be determined in 58% of the patients. The sympathetic gain as well as the burst incidence differed significantly between patients and healthy volunteers. Missing BRSSY-incidence was associated with higher burst incidence. Conclusion: Cardiovagal BRS indices have limited value in differentiating healthy and heart failure subjects. Incalculable values among patients indicate more severe disease state. BRSSY-incidence does separate healthy and diseased population, the missing BRSSY-incidence values are related to increased sympathetic activity. Orv Hetil. 2021; 162(3): 91–98.
Absztrakt: A szívelégtelenség napjaink egyik fontos népbetegsége. Zajlása során a neurohumoralis szabályzás kórossá válik. A cardiovascularis autonóm regulációt a csökkenő paraszimpatikus aktivitás és a fokozott szimpatikus aktivitás jellemzi. A paraszimpatikus (cardiovagalis) hatásokat jól tükrözi a pulzusszám, a szimpatikus aktivitás azonban nehezen vizsgálható. A vázizomzathoz haladó vazomotorrostokat tartalmazó perifériás idegek mikroneurográfiás vizsgálata az „izom szimpatikus idegaktivitásról” (MSNA) szolgáltat közvetlen információt. Az MSNA jól tükrözi a szív felé irányuló szimpatikus aktivitást, s jól korrelál a keringő katecholaminszintekkel is. Az utóbbival szemben azonban a rövid távú, pillanatszerűen zajló szimpatikus válaszok tanulmányozását is lehetővé teszi. Számos kórképben (hypertensio, obesitas, szívizom-ischaemia, veseelégtelenség) figyeltek meg fokozott MSNA-t. Szívelégtelenségben szoros kapcsolatot mutat a klinikai súlyossággal, és erős prognosztikus értékkel bír. Közleményünkben az MSNA-vizsgálat történetét, élettani hátterét és klinikai jelentőségét mutatjuk be. Orv Hetil. 2020; 161(29): 1190–1199.
Introduction: Increased muscle sympathetic nerve activity (MSNA) indicates an adverse outcome in heart failure. Decreased baroreflex modulation of MSNA is a well-known feature of the disease. The determinability of cardiovagal baroreflex sensitivity (BRS) in heart failure is low, however, the determinability of sympathetic BRS is not known. Methods:We have assessed the spontaneous, MSNA burst incidence-based baroreflex index (BRSsymp) in 33 stable heart failure patients and in 10 healthy controls using the traditional r ≥ .5 cutoff for acceptable individual diastolic pressure-burst incidence slopes, and also a more stringent r ≥ .7 cutoff. We have also assessed the influence of 6/min breathing. Results:The determinability of BRSsymp in heart failure patients was 64% during spontaneous breathing with r ≥ .5 cutoff, and 39% using the r ≥ .7 cutoff. The determinability of these indices further decreased during 6/min breathing, dropping to 29% with the r ≥ .7 cutoff. In contrast, the determinability of the cardiovagal BRS indices increased significantly with 6/min breathing (from 24% to 66%; p < .001).Patients who still had determinable BRSsymp at the r ≥ .7 cutoff had a significantly lower baseline burst incidence than those with an undeterminable index (70 ± 14 vs. 89 ± 10 burst/100 cycles; p < .002). Neither the 6/min breathing, nor the r ≥ .7 cutoff limit influenced the high availability of BRSsymp in healthy subjects. Conclusion:The determinability of BRSsymp in heart failure patients is limited, especially with the 0.7 limit for correlation. Undeterminable BRSsymp in patients is associated with higher sympathetic activity. 6/min breathing improves the determinability of cardiovagal BRS indices, but not that of BRSsymp.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.