What is the clinical evidence from this study?

Study design: Other. Population: Chronic coronary pressure overload and severe left ventricular hypertrophy (n=14). Intervention: Acetylcholine, nitroglycerin, and reactive hyperemia vs. Control dogs. Primary outcome: Coronary diameter response to acetylcholine (p=<0.05).

What does this research mean for the field?

In conscious dogs with chronic coronary pressure overload, endothelial control is selectively impaired in large coronary arteries for both flow-mediated and receptor-mediated functions, while resistance vessels are spared. Novelty: ClaimNovelty.INCREMENTAL. Consensus alignment: ConsensusAlignment.NEUTRAL.

What question did this study set out to answer?

To determine whether chronic coronary pressure overload and left ventricular hypertrophy impair endothelial regulation in large coronary arteries compared to resistance microvessels.

February 1, 1998AJP Heart and Circulatory Physiology

Selective large coronary endothelial dysfunction in conscious dogs with chronic coronary pressure overload

Q: What are the key findings of this study?

In conscious dogs with chronic coronary pressure overload, acetylcholine-induced increases in coronary diameter were significantly reduced compared to controls (+1.9% vs +5.9%, P<0.05).

Q: What does this research mean for the field?

In conscious dogs with chronic coronary pressure overload, endothelial control is selectively impaired in large coronary arteries for both flow-mediated and receptor-mediated functions, while resistance vessels are spared. Novelty: ClaimNovelty.INCREMENTAL. Consensus alignment: ConsensusAlignment.NEUTRAL.

Q: What question did this study set out to answer?

To determine whether chronic coronary pressure overload and left ventricular hypertrophy impair endothelial regulation in large coronary arteries compared to resistance microvessels.

View Full Paper

Ask AI

Bookmark

Key result

In conscious dogs with chronic coronary pressure overload, acetylcholine-induced increases in coronary diameter were significantly reduced compared to controls (+1.9% vs +5.9%, P<0.05).

Why the study?

Does chronic coronary pressure overload impair coronary endothelial function in conscious dogs?

Population

14 conscious dogs

Comparison

Acetylcholine, nitroglycerin, and a 20-s… vs Control dogs

Design

Preclinical

Authors

BGBijan GhalehInserm LHLuc HittingerHôpitaux Universitaires Henri-Mondor SKSong‐Jung KimUniversidade Federal de Minas Gerais

Discussion

Member takes

Implication

May suggest endothelial impairment in pressure overload; leaves open translation to human coronary disease.

Key Points

To determine whether chronic coronary pressure overload and left ventricular hypertrophy impair endothelial regulation in large coronary arteries compared to resistance microvessels.
Assessed 7 conscious dogs with chronic coronary pressure overload (CCPO) induced by supravalvular aortic banding and 7 control dogs.
Measured ultrasonic coronary diameter and Doppler coronary blood flow following acetylcholine (3 µg/kg i.v.), nitroglycerin (25 µg/kg i.v.), and 20-second reactive hyperemia occlusions.
Conducted histological analyses of both large conduit coronary arteries and small intramyocardial resistance arterioles.
Acetylcholine-induced coronary dilation was reduced in CCPO dogs (+1.9 ± 0.9%) compared to controls (+5.9 ± 1.7%, P < 0.05), and reactive hyperemia dilation was blunted (+2.1 ± 0.8% vs. +6.8 ± 1.8%, P < 0.01), whereas blood flow increases and nitroglycerin responses were preserved.
Peak systolic coronary blood flow velocity was significantly elevated in CCPO dogs (94 ± 17 cm/s) compared with controls (35 ± 7 cm/s, P < 0.01), driven by higher systolic coronary perfusion pressure (215 vs. 130 mmHg).
Histology revealed intimal thickening and endothelial disruption exclusively in large coronary arteries, while small intramyocardial arterioles were completely spared.

Structured PICO

Does chronic coronary pressure overload impair coronary endothelial function in conscious dogs?

Population

14 conscious dogs (7 with severe left ventricular hypertrophy and chronic coronary pressure overload due to supravalvular aortic banding, 7 control dogs)

Intervention

Acetylcholine (3 micrograms/kg i.v.), nitroglycerin (25 micrograms/kg i.v.), and a 20-s coronary artery occlusion (reactive hyperemia)

Comparator

Control dogs

Outcome

Coronary vascular responses (coronary diameter and coronary blood flow)surrogate

Main Result

Absolute Event Rate: 1.9% vs 5.9%

p-value: p=<0.05

Chronic coronary pressure overload in dogs leads to selective large coronary endothelial dysfunction, likely due to morphological changes from elevated systolic perfusion pressure and altered flow patterns.

Cite This Study

Ghaleh et al. (1998) studied Chronic coronary pressure overload and severe left ventricular hypertrophy (n=14). Acetylcholine, nitroglycerin, and reactive hyperemia vs. Control dogs was evaluated on Coronary diameter response to acetylcholine (p=<0.05). In conscious dogs with chronic coronary pressure overload, acetylcholine-induced increases in coronary diameter were significantly reduced compared to controls (+1.9% vs +5.9%, P<0.05).

synapsesocial.com/papers/6a1757bb3510de12de8d7cbd https://doi.org/10.1152/ajpheart.1998.274.2.h539

Topics

Coronary CT angiography

View Full Paper

Ask AI

Bookmark

Selective large coronary endothelial dysfunction in conscious dogs with chronic coronary pressure overload

Discussion

Member takes

Implication

Key Points

Structured PICO

Main Result

Cite This Study

Topics

Selective large coronary endothelial dysfunction in conscious dogs with chronic coronary pressure overload

Discussion

Member takes

Implication

Key Points

Structured PICO

Main Result

Cite This Study

Also Consider

Topics

Also Consider