Exercise-Induced Bundle Branch Block - an Infrequent Incidence

We describe an elderly woman who underwent a treadmill test preoperatively and was found to have Exercise-induced Left Bundle Branch Block without chest pain. Coronary angiogram was done which revealed a 70% stenosis in the fi rst diagonal branch of Left Anterior Descending Artery and a 40% lesion in proximal Right Coronary Artery. Available literature attributes rate-dependent transient conduction defects to obstructive lesions of coronary arteries, slow arterial blood fl ow, vasospasms as well as pathology in the Bundle of His.

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Experimental Production of Rate-Dependent Bundle Branch Block in the Canine Heart

Circulation Research ◽

10.1161/01.res.34.5.730 ◽

1974 ◽

Vol 34 (5) ◽

pp. 730-742 ◽

Cited By ~ 25

Author(s):

MARCELO V. ELIZARI ◽

GERARDO J. NAU ◽

RAÚL J. LEVI ◽

JULIO O. LÁZZARI ◽

M. SUSANA HALPERN ◽

...

Keyword(s):

Experimental Production ◽

Canine Heart ◽

Bundle Branch Block ◽

Rate Dependent

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Pulmonary gas exchange during exercise in women: effects of exercise type and work increment

Journal of Applied Physiology ◽

10.1152/jappl.2000.89.2.721 ◽

2000 ◽

Vol 89 (2) ◽

pp. 721-730 ◽

Cited By ~ 70

Author(s):

Susan R. Hopkins ◽

Rebecca C. Barker ◽

Tom D. Brutsaert ◽

Timothy P. Gavin ◽

Pauline Entin ◽

...

Keyword(s):

Cardiac Output ◽

Gas Exchange ◽

Blood Gases ◽

Random Order ◽

Pulmonary Gas Exchange ◽

Male Athletes ◽

Prediction Limit ◽

Fast Running ◽

Arterial Blood ◽

Exercise Induced

Exercise-induced arterial hypoxemia (EIAH) has been reported in male athletes, particularly during fast-increment treadmill exercise protocols. Recent reports suggest a higher incidence in women. We hypothesized that 1-min incremental (fast) running (R) protocols would result in a lower arterial Po 2 (PaO2 ) than 5-min increment protocols (slow) or cycling exercise (C) and that women would experience greater EIAH than previously reported for men. Arterial blood gases, cardiac output, and metabolic data were obtained in 17 active women [mean maximal O2 uptake (V˙o 2 max) = 51 ml · kg−1 · min−1]. They were studied in random order (C or R), with a fastV˙o 2 max protocol. After recovery, the women performed 5 min of exercise at 30, 60, and 90% ofV˙o 2 max (slow). One week later, the other exercise mode (R or C) was similarly studied. There were no significant differences in V˙o 2 maxbetween R and C. Pulmonary gas exchange was similar at rest, 30%, and 60% of V˙o 2 max. At 90% ofV˙o 2 max, PaO2 was lower during R (mean ± SE = 94 ± 2 Torr) than during C (105 ± 2 Torr, P < 0.0001), as was ventilation (85.2 ± 3.8 vs. 98.2 ± 4.4 l/min btps, P < 0.0001) and cardiac output (19.1 ± 0.6 vs. 21.1 ± 1.0 l/min, P < 0.001). Arterial Pco 2 (32.0 ± 0.5 vs. 30.0 ± 0.6 Torr, P < 0.001) and alveolar-arterial O2 difference (A-aDo 2; 22 ± 2 vs. 16 ± 2 Torr, P < 0.0001) were greater during R. PaO2 and A-aDo 2 were similar between slow and fast. Nadir PaO2 was ≤80 Torr in four women (24%) but only during fast-R. In all subjects, PaO2 atV˙o 2 max was greater than the lower 95% prediction limit calculated from available data in men ( n = 72 C and 38 R) for both R and C. These data suggest intrinsic differences in gas exchange between R and C, due to differences in ventilation and also efficiency of gas exchange. The PaO2 responses to R and C exercise in our 17 subjects do not differ significantly from those previously observed in men.

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Rate-Dependent Left Bundle Branch Block in an Ambulatory Surgery Patient

A & A Case Reports ◽

10.1213/xaa.0000000000000435 ◽

2017 ◽

Vol 8 (4) ◽

pp. 81-85

Author(s):

Ashraf Farag ◽

Justin Tsai ◽

Sam Deeb ◽

Deidre Putman-Garcia ◽

John D. Wasnick ◽

...

Keyword(s):

Left Bundle Branch Block ◽

Ambulatory Surgery ◽

Bundle Branch Block ◽

Rate Dependent ◽

Surgery Patient

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Coca chewing for exercise: hormonal and metabolic responses of nonhabitual chewers

Journal of Applied Physiology ◽

10.1152/jappl.1996.81.5.1901 ◽

1996 ◽

Vol 81 (5) ◽

pp. 1901-1907 ◽

Cited By ~ 7

Author(s):

Roland Favier ◽

Esperanza Caceres ◽

Laurent Guillon ◽

Brigitte Sempore ◽

Michel Sauvain ◽

...

Keyword(s):

Heart Rate ◽

Gas Exchange ◽

Oxygen Uptake ◽

Metabolic Responses ◽

Physiological Data ◽

Respiratory Gas Exchange ◽

Gum Chewing ◽

Arterial Blood ◽

Before And After ◽

Exercise Induced

Favier, Roland, Esperanza Caceres, Laurent Guillon, Brigitte Sempore, Michel Sauvain, Harry Koubi, and Hilde Spielvogel. Coca chewing for exercise: hormonal and metabolic responses of nonhabitual chewers. J. Appl. Physiol. 81(5): 1901–1907, 1996.—To determine the effects of acute coca use on the hormonal and metabolic responses to exercise, 12 healthy nonhabitual coca users were submitted twice to steady-state exercise (∼75% maximal O2 uptake). On one occasion, they were asked to chew 15 g of coca leaves 1 h before exercise, whereas on the other occasion, exercise was performed after 1 h of chewing a sugar-free chewing gum. Plasma epinephrine, norepinephrine, insulin, glucagon, and metabolites (glucose, lactate, glycerol, and free fatty acids) were determined at rest before and after coca chewing and during the 5th, 15th, 30th, and 60th min of exercise. Simultaneously to these determinations, cardiorespiratory variables (heart rate, mean arterial blood pressure, oxygen uptake, and respiratory gas exchange ratio) were also measured. At rest, coca chewing had no effect on plasma hormonal and metabolic levels except for a significantly reduced insulin concentration. During exercise, the oxygen uptake, heart rate, and respiratory gas exchange ratio were significantly increased in the coca-chewing trial compared with the control (gum-chewing) test. The exercise-induced drop in plasma glucose and insulin was prevented by prior coca chewing. These results contrast with previous data obtained in chronic coca users who display during prolonged submaximal exercise an exaggerated plasma sympathetic response, an enhanced availability and utilization of fat (R. Favier, E. Caceres, H. Koubi, B. Sempore, M. Sauvain, and H. Spielvogel. J. Appl. Physiol. 80: 650–655, 1996). We conclude that, whereas coca chewing might affect glucose homeostasis during exercise, none of the physiological data provided by this study would suggest that acute coca chewing in nonhabitual users could enhance tolerance to exercise.

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Comparison of Myocardial Infarction with Sequential Ligation of the Left Anterior Descending Artery and Its Diagonal Branch in Dogs and Sheep

The International Journal of Artificial Organs ◽

10.1177/039139880302600411 ◽

2003 ◽

Vol 26 (4) ◽

pp. 351-357 ◽

Cited By ~ 10

Author(s):

W.G. Kim ◽

Y.C. Shin ◽

S.W. Hwang ◽

C. Lee ◽

C.Y. Na

Keyword(s):

Myocardial Infarction ◽

Coronary Artery ◽

Pulmonary Artery ◽

Left Ventricular ◽

Coronary Artery Ligation ◽

Suitable Model ◽

Artery Ligation ◽

Diagonal Branch ◽

Left Anterior Descending Artery ◽

Arterial Blood

We report a comparison of the effects of myocardial infarction in dogs and sheep using sequential ligation of the left anterior descending artery (LAD) and its diagonal branch (DA), with hemodynamic, ultrasonographic and pathological evaluations. Five animals were used in each group. After surgical preparation, the LAD was ligated at a point approximately 40% of the distance from the apex to the base of the heart, and after one hour, the DA was ligated at the same level. Hemodynamic and ultrasonographic measurements were performed preligation, 30 minutes after LAD ligation, and 1 hour after DA ligation. As a control, two animals in each group were used for the simultaneous ligation of the LAD and the DA. Two months after the coronary ligation, the animals were evaluated as previously, and killed for postmortem examination of their hearts. All seven animals in the dog group survived the experimental procedures, while in the sheep group only animals with sequential ligation of the LAD and DA survived. Statistically significant decreases in systemic arterial blood pressure and cardiac output, and an increase in the pulmonary artery capillary wedge pressure (PACWP) were observed one hour after sequential ligation of the LAD and its DA in the sheep, while only systemic arterial pressures decreased in the dog. Ultrasonographic analyses demonstrated variable degrees of anteroseptal dyskinesia and akinesia in all sheep, but in no dogs. Data two months after coronary artery ligation showed significant increases in central venous pressure, pulmonary artery pressure, and PACWP in the sheep, but not in the dog. Left ventricular end-diastolic dimension and left ventricular end-systolic dimension in ultrasonographic studies were also increased only in the sheep. Pathologically, the well-demarcated thin-walled transmural anteroseptal infarcts with chamber enlargement were clearly seen in all specimens of sheep, and only-mild-to-moderate chamber enlargements with endocardial fibrosis were observed in the dog hearts. In conclusion, this study confirms that the dog is not a suitable model for myocardial infarction with failure by coronary artery ligation despite negligent operative mortality, when compared directly with an ovine model.

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