Interaction between respiration and right versus left ventricular volumes at rest and during exercise : a real-time cardiac magnetic resonance study

Claessen, Guido; Claus, Piet; Delcroix, Marion; Bogaert, Jan; La Gerche, Andre; Heidbuchel, Hein

doi:10.1152/AJPHEART.00752.2013

Title

Interaction between respiration and right versus left ventricular volumes at rest and during exercise : a real-time cardiac magnetic resonance study

Author

Claessen, Guido

Claus, Piet

Delcroix, Marion

Bogaert, Jan

La Gerche, Andre

Heidbuchel, Hein

Abstract

Breathing-induced changes in intrathoracic pressures influence left ventricular (LV) and right ventricular (RV) volumes, the exact nature and extent of which have not previously been evaluated in humans. We sought to examine this "respiratory pump" using novel real-time cardiac magnetic resonance (CMR) imaging. Eight healthy subjects underwent serial multislice real-time CMR during normal breathing, breath holding, and the Valsalva maneuver. Subsequently, a separate cohort of nine subjects underwent real-time CMR at rest and during incremental exercise. LV and RV end-diastolic volume (EDV) and end-systolic volume (ESV) and diastolic and systolic eccentricity indexes were determined at peak inspiration and expiration. During normal breathing, inspiration resulted in an increase in RV volumes [RVEDV: +18 +/- 8%, RVESV: +14 +/- 12%, and RV stroke volume (SV): +21 +/- 10%, P < 0.01] and an opposing decrease in LV volumes (P < 0.0001 for interaction). During end-inspiratory breath holding, RV SV decreased by 9 +/- 10% (P = 0.046), whereas LV SV did not change. During the Valsalva maneuver, volumes decreased in both ventricles (RVEDV: -29 +/- 11%, RVESV: -16 +/- 14%, RV SV: -36 +/- 14%, LVEDV: -22 +/- 17%, and LV SV: -25 +/- 17%, P < 0.01). The reciprocal effect of respiration on LV and RV volumes was maintained throughout exercise. The diastolic and systolic eccentricity indexes were greater during inspiration than during expiration, both at rest and during exercise (P < 0.0001 for both). In conclusion, ventricular volumes oscillate with respiratory phase such that RV and LV volumes are maximal at peak inspiration and expiration, respectively. Thus, interpretation of RV versus LV volumes requires careful definition of the exact respiratory time point for proper interpretation, both at rest and during exercise.

Language

English

Source (journal)

American journal of physiology : heart and circulatory physiology / American Physiological Society. - Bethesda, Md, 1977, currens

Publication

Bethesda, Md : 2014

ISSN

0363-6135 [print]

0363-6135

1522-1539 [online]

DOI

10.1152/AJPHEART.00752.2013