TITLE

Optimisation of atrioventricular delay during exercise improves cardiac output in patients stabilised with cardiac resynchronisation therapy

AUTHOR(S)
Jing Ping Sun; Lee, Alex Pui-Wai; Grimm, Richard A.; Ming-Jui Hung; Xing Sheng Yang; DeLurgio, David; Leon, Angel R.; Merlino, John D.; Cheuk-Man Yu
PUB. DATE
January 2012
SOURCE
Heart;Jan2012, Vol. 98 Issue 1, p54
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Background Atrioventricular (AV) delay in cardiac resynchronisation therapy (CRT) recipients are typically optimised at rest. However, there are limited data on the impact of exercise-induced changes in heart rate on the optimal AV delay and left ventricular function. Methods and results The authors serially programmed AV delays in 41 CRT patients with intrinsic sinus rhythm at rest and during two stages of supine bicycle exercise with heart rates at 20 bpm (stage I) and 40 bpm (stage II) above baseline. The optimal AV delay during exercise was determined by the iterative method to maximise cardiac output using Doppler echocardiography. Results were compared to physiological change in PR intervals in 56 normal controls during treadmill exercise. The optimal AV delay was progressively shortened (p<0.05) with escalating exercise level (baseline: 123±26 ms vs stage I: 102±24 ms vs stage II: 70±22 ms, p<0.05). AV delay optimisation led to a significantly higher cardiac output than without optimisation did during stage I (6.2±1.2 l/min vs 5.2±1.2 l/min, p<0.001) and stage II (6.8±1.6 l/min vs 5.9±1.3 l/min, p<0.001) exercise. A linear inverse relationship existed between optimal AV delays and heart rates in CRT patients (AV delay=241-1.61 x heart rate, R²=0.639, p<0.001) and healthy controls (R²=0.646, p<0.001), but the slope of regression was significantly steeper in CRT patients (p<0.001). Conclusions Haemodynamically optimal AV delay shortened progressively with increasing heart rate during exercise, which suggests the need for programming of rate-adaptive AV delay in CRT recipients.
ACCESSION #
69749227

 

Related Articles

  • Influence of Short Atrioventricular Delay on Late Diastolic Transmitral Flow and Stroke Volume. Ronaszeki, Aladar; Denef, Boudewijn; Ector, Hugo; Aubert, Andre E.; Werf, Frans Van De; De Geest, Hilaire // Angiology;Jan1992, Vol. 43 Issue 1, p32 

    Atrial transport function and the corresponding transmitral flow and stroke volume depend on the timing of atrial contraction. To study the influence of short atrioventricular delay (AVD) on these hemodynamic parameters, transmitral flow velocity (by pulsed wave Doppler) and aortic flow (by...

  • Spectral Energy of ECG Morphologic Differences to Predict Death. Phil Sung; Benjamin Scirica; David Morrow; John Guttag // Cardiovascular Engineering: An International Journal;Mar2009, Vol. 9 Issue 1, p18 

    Abstract  Unstable conduction system bifurcations following ischemia and infarction are associated with variations in the electrocardiographic activity spanning the heart beat. In this paper, we investigate a spectral energy measure of morphologic differences (SE-MD) that quantifies...

  • A Combination of Atrioventricular Block and Sinoatrial Block in a Horse. Rezakhani, A.; Godarzi, M.; Naeini, I. Tabatabei // Acta Veterinaria Scandinavica;2005, Vol. 46, p173 

    The article presents a study on the process of carrying out a routine check up examination on a group of horses of a riding school in Shiraz, Iran. It is a horse demonstrated frequent long pauses in heart rate of 33 beats per minute on auscultation. A base apex electrocardiogram was recorded to...

  • THE DELAY IN TRANSMISSION OF THE ATRIAL IMPULSE TO THE VENTRICLE. Di Palma, Joseph R. // Angiology;Aug1958, Vol. 9 Issue 4, p219 

    Two direct atrial action potentials were recorded in the anesthetized dog. One potential was made at the SA node as a monophasic current; the other was made at the area of the AV node as a diphasic current. The time of excitation of the AV node could be seen on these records. Thus the following...

  • Stereologic study of the sinoatrial node of rats – age related changes. de Melo, Silvana Regina; de Souza, Romeu Rodrigues; Mandarim-de-Lacerda, Carlos Alberto // Biogerontology;Dec2002, Vol. 3 Issue 6, p383 

    Changes in the sinoatrial node represent the major mechanism of sudden death in humans, and because of the sparse knowledge about the effects of aging on this structure, light microscopic and quantitative studies of the sinoatrial node were undertaken. Twenty-one hearts were studied, seven rat...

  • Effect of Pindolol and Propranolol on Sinus Node Recovery Time and Atrioventricular Conduction Intervals. Kostis, John B.; Binenbaum, Steve Z.; Oliveri, Philip; Sclar, Craig; Hosler, Maryhelen // Angiology;Jun1987, Vol. 38 Issue 6, p427 

    In a randomized, observer-blind study, the effect of incremental doses of pindolol 0.001, 0.002, 0.003, and 0.004 mg/kg IV and propranolol 0.01, 0.02, 0.03, and 0.04 mg/kg IV on SA nodal recovery time (SNRT) and atrioventricular conduction interval (AH) was assessed in 20 patients (15 men and 5...

  • Second-degree atrioventricular block revisited. Barold, S. Serge; Herweg, Bengt // Herzschrittmachertherapie und Elektrophysiologie;Dec2012, Vol. 23 Issue 4, p296 

    Type I second-degree atrioventricular (AV) block describes visible, differing, and generally decremental AV conduction. The literature contains numerous differing definitions of second-degree AV block, especially Mobitz type II second-degree AV block. The widespread use of numerous disparate...

  • JCDR: Case Report Successfully Ablated Atrioventricular Nodal Reentrant Tachycardia in Unconventional Presentation. Jun-Hua Wang; Cong-Chun Huang; Wei-Jie Tan; Chao-Zhong Liu; Jin-Jin Sun; Hui-Lan Luo // Journal of Cardiovascular Disease Research (Medknow Publications;Jan-Feb2010, Vol. 1 Issue 1, p40 

    Background:—Sometime, it's difficult to distinguish the electrophysiological mechanism of some tachycardia, and so, influencing the efficacy and safety of ablation operation. Therefore, it's helpful to analysis some tachycardia in particular mechanism, as in this case. Methods and...

  • SA node.  // Taber's Cyclopedic Medical Dictionary;2005, p1942 

    The article presents a definition for the term "SA node," which refers to sinoatrial node of the heart.

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sign out of this library

Other Topics