Document Detail

Effects of depth and chest volume on cardiac function during breath-hold diving.
MedLine Citation:
PMID:  19424715     Owner:  NLM     Status:  MEDLINE    
Cardiac response to breath-hold diving in human beings is primarily characterized by the reduction of both heart rate and stroke volume. By underwater Doppler-echocardiography we observed a "restrictive/constrictive" left ventricular filling pattern compatible with the idea of chest squeeze and heart compression during diving. We hypothesized that underwater re-expansion of the chest would release heart constriction and normalize cardiac function. To this aim, 10 healthy male subjects (age 34.2 +/- 10.4) were evaluated by Doppler-echocardiography during breath-hold immersion at a depth of 10 m, before and after a single maximal inspiration from a SCUBA device. During the same session, all subjects were also studied at surface (full-body immersion) and at 5-m depth in order to better characterize the relationship of echo-Doppler pattern with depth. In comparison to surface immersion, 5-m deep diving was sufficient to reduce cardiac output (P = 0.042) and increase transmitral E-peak velocity (P < 0.001). These changes remained unaltered at a 10-m depth. Chest expansion at 10 m decreased left ventricular end-systolic volume (P = 0.024) and increased left ventricular stroke volume (P = 0.024). In addition, it decreased transmitral E-peak velocity (P = 0.012) and increased deceleration time of E-peak (P = 0.021). In conclusion the diving response, already evident during shallow diving (5 m) did not progress during deeper dives (10 m). The rapid improvement in systolic and diastolic function observed after lung volume expansion is congruous with the idea of a constrictive effect on the heart exerted by chest squeeze.
Claudio Marabotti; Alessandro Scalzini; Danilo Cialoni; Mirko Passera; Andrea Ripoli; Antonio L'Abbate; Remo Bedini
Related Documents :
9217915 - The hemodynamic manifestation of normal myocardial relaxation. a framework for experime...
16028255 - Left ventricular diastolic function compared with t2* cardiovascular magnetic resonance...
21854435 - Endothelial-mediated coronary flow reserve and its relation to mitral annular tissue do...
22534055 - Changes in left ventricular morphology and function after mitral valve surgery.
24132645 - Atrial fibrillation in heart failure: catheter and surgical interventional therapies.
12094195 - Impact of sex and its interaction with age on the management of and outcome for patient...
Publication Detail:
Type:  Clinical Trial; Journal Article; Research Support, Non-U.S. Gov't     Date:  2009-05-08
Journal Detail:
Title:  European journal of applied physiology     Volume:  106     ISSN:  1439-6327     ISO Abbreviation:  Eur. J. Appl. Physiol.     Publication Date:  2009 Jul 
Date Detail:
Created Date:  2009-07-02     Completed Date:  2009-10-01     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  100954790     Medline TA:  Eur J Appl Physiol     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  683-9     Citation Subset:  IM    
UO Cardiovascolare-UTIC Ospedale di Cecina, 57023 Cecina (LI), Italy.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Diving / physiology*
Echocardiography, Doppler
Heart / physiology*
Hydrostatic Pressure
Inspiratory Reserve Volume / physiology
Lung Volume Measurements
Middle Aged
Respiratory Mechanics / physiology*
Thorax / physiology*
Young Adult

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Exhaustive exercise causes an anti-inflammatory effect in skeletal muscle and a pro-inflammatory eff...
Next Document:  Effect of in-water recompression with oxygen to 6 msw versus normobaric oxygen breathing on bubble f...