Asymmetry of the acceleration and deceleration capacity of heart rate is strongly dependent on ventricular premature complexes / Die Abhängigkeit der Asymmetrie von „Akzelerations- und Dezelerationskapazität” der Herzfrequenz vom Auftreten ventrikulärer Extrasystolen

Background: Increased parasympathetic activity is thought to play important roles in syncope events of patients with vasovagal syncope (VVS). However, direct measurements of the vagal control are difficult. The novel deceleration capacity (DC) of heart rate measure has been used to characterize the vagal modulation. This study aimed to assess vagal control in patients with VVS and evaluate the diagnostic value of the DC in VVS. Methods: Altogether, 161 consecutive patients with VVS (43±15 years; 62 males) were enrolled. Tilt table test was positive in 101 and negative in 60 patients. Sixty-five healthy subjects were enrolled as controls. DC and heart rate variability in 24-hour ECG, echocardiogram, and biochemical examinations were compared between the syncope and control groups. Results: DC was significantly higher in the syncope group than in the control group (9.6±3.3 versus 6.5±2.0 ms, P <0.001). DC was similarly increased in patients with VVS with a positive and negative tilt table test (9.7±3.5 and 9.4±2.9 ms, P =0.614). In multivariable logistic regression analyses, DC was independently associated with syncope (odds ratio=1.518 [95% CI, 1.301–1.770]; P =0.0001). For the prediction of syncope, the area under curve analysis showed similar values when comparing single DC and combined DC with other risk factors ( P =0.1147). From the receiver operator characteristic curves for syncope discrimination, the optimal cutoff value for the DC was 7.12 ms. Conclusions: DC>7.5 ms may serve as a good tool to monitor cardiac vagal activity and discriminate VVS, particularly in those with negative tilt table test.

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Deceleration capacity of heart rate and periodic repolarization dynamics during normobaric hypoxia

Scandinavian Journal of Medicine and Science in Sports ◽

10.1111/sms.13670 ◽

2020 ◽

Vol 30 (6) ◽

pp. 1087-1089

Author(s):

Wolfgang Hamm ◽

Florian Maier ◽

Sari Kassem ◽

Dominik Schüttler ◽

Axel Bauer ◽

...

Keyword(s):

Heart Rate ◽

Normobaric Hypoxia ◽

Deceleration Capacity ◽

Repolarization Dynamics ◽

Periodic Repolarization Dynamics

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A Novel and Simple Exercise Test Parameter to Assess Responsiveness to Cardiac Resynchronization Therapy

Diagnostics ◽

10.3390/diagnostics10110920 ◽

2020 ◽

Vol 10 (11) ◽

pp. 920

Author(s):

Alina-Ramona Cozlac ◽

Lucian Petrescu ◽

Simina Crisan ◽

Constantin Tudor Luca ◽

Cristina Vacarescu ◽

...

Keyword(s):

Heart Rate ◽

Cardiac Resynchronization Therapy ◽

Exercise Test ◽

Heart Rate Recovery ◽

Area Under The Curve ◽

Left Ventricular ◽

Cardiac Resynchronization ◽

Reverse Remodeling ◽

Resynchronization Therapy ◽

Acceleration And Deceleration

This study assessed the value of heart rate recovery index (HRRI), a new parameter of an exercise test, as the predictor of response to cardiac resynchronization therapy (CRT). Methods: Consecutive patients receiving a CRT device were followed up after implantation and every 6 months. An effort test (ET) was quantified by minimum heart rate/maximum heart rate, as well as acceleration and deceleration times. HRRI was calculated as the ratio between acceleration and deceleration time (AT/DT) and compared to outcome. We used logistic regression to assess the predictive value of HRRI for responders and non-responders to CRT. The area under the curve (AUC) was computed to distinguish between positive and negative outcomes. Results: A total of 109 patients (74 men, mean age 63.3 ± 9.8 years) were analyzed; permanent long-term fusion CRT pacing was possible in 65 patients. Patients were assigned to two groups: responders and non-responders (98/11 patients). During a mean follow-up of 36 months, 545 ETs were performed. HRRI was significantly higher in responders versus non-responders (3.16 ± 2 vs. 1.4 ± 0.5, p < 0.001). The optimal cutoff value for HRRI as a predictor of CRT response was 1.51 (area under the receiver operating characteristic (ROC) curve = 0.844). Responders had significant left-ventricular (LV) reverse remodeling (LV end-diastolic volume = 240 ± 90 mL vs. 217 ± 89 mL, p < 0.001) and higher LV ejection fraction (26 ± 5.8% vs. 35 ± 8.7%, p < 0.001). Conclusions: HRRI computation during routine ET is useful for the evaluation of responsiveness to CRT.

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Dogs poisoned with Nerium oleander fresh leaves: clinical and electrocardiographic findings

Ciência Rural ◽

10.1590/0103-8478cr20160970 ◽

2017 ◽

Vol 47 (6) ◽

Cited By ~ 1

Author(s):

Annelise Carla Camplesi ◽

Carolina Bellodi ◽

José Javier Mesa Socha ◽

Mário Roberto Hatayde ◽

Márcia Ferreira da Rosa Sobreira ◽

...

Keyword(s):

Heart Rate ◽

Digestive System ◽

Sinus Bradycardia ◽

Ornamental Plants ◽

Nerium Oleander ◽

Mixed Breed ◽

Ventricular Premature Complexes ◽

Electrocardiographic Findings ◽

Loss Of Appetite ◽

Clinical Changes

ABSTRACT: Nerium oleander is distributed worldwide, mainly in tropical and subtropical regions. These shrubs are frequently used as ornamental plants. However, they contain more than 30 cardiac glycosides that can cause serious toxic effects in dogs. The objective of this study was to report the clinical and electrocardiographic alterations in dogs experimentally poisoned with N. oleander. Ten adult, healthy, mixed-breed dogs weighing 10-25kg and aged 3-6 years were selected for the study. We orally administered 0.25g kg-1 of fresh ground leaves of N. oleander to the dogs. No dog died after the ingestion, but all exhibited signs of poisoning such as vomiting, sialorrhea, nausea, apathy, conjunctiva congestion, dehydration, abdominal pain, tremors, diarrhea, loss of appetite, and tenesmus. Electrocardiogram revealed occurrence of several types of arrhythmias: sinus bradycardia, second-degree atrioventricular block, paroxysmal ventricular tachycardia, and ventricular premature complexes. Systolic blood pressure, as well as heart rate, decreased in the first 24 hours. The present study concluded that a single dose of 0.25g kg-1 of N. oleander green leaves is sufficient to cause a moderate intoxication in dogs, with nonspecific clinical changes mainly related to the digestive system and heart rate, thus demonstrating the importance of this type of intoxication in the list of differential diagnoses of small animals routine.

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