Comparison of myocardial protection with nifedipine and potassium

P. G. Magee, J. T. Flaherty, T. J. Bixler, D. Glower, T. J. Gardner, B. H. Bukley, Vincent L Gott

Research output: Contribution to journalArticle

Abstract

Nifedipine, a slow-channel calcium blocker, is thought to provide useful myocardial protection during prolonged total ischemia and reperfusion. An isolated, isovolumic, feline heart model was used to assess the effectiveness of nifedipine in both cardioplegic (100 μg/10 ml) and noncardioplegic (10 μg/10 ml) doses for providing myocardial preservation during 90 minutes of hyperthermic ischemic arrest and 45 minutes of normothermic reperfusion. Use of nifedipine was compared to hypothermia (27°C) alone and to hypothermia with potassium cardioplegia. Ventricular function was assessed by recovery of isovolumic left ventricular developed pressure and dP/dt. Myocardial carbon dioxide tension (PCO2) and myocardial oxygen tension (PO2) were measured by mass spectrometry. Potassium cardioplegia and the higher dose of nifedipine resulted in immediate asystole. The rates of rise of PCO2 were greatest in the group receiving 10 μg nifedipine and in the control group. The rates of rise in the two cardioplegic groups were significantly lower. Recovery of ventricular function was significantly lower with low-dose nifedipine than with potassium cardioplegia. Higher dose nifedipine resulted in a return of function, which was no different than with potassium cardioplegia. Morphologic protection was better with higher dose nifedipine and potassium cardioplegia than with either low-dose cardioplegia or hypothermia alone. These results demonstrate that nifedipine in a cardioplegic dose results in preservation of myocardial structure and function that is similar to that obtained with potassium cardioplegia. In lower noncardioplegic dose, nifedipine does not appear to offer additional protection compared to hypothermia alone. Whether persistent depression of ventricular contractility will limit nifedipine's clinical usefulness as a myocardial protection agent will require further study.

Original languageEnglish (US)
JournalCirculation
Volume60
Issue number2 II
StatePublished - 1979
Externally publishedYes

Fingerprint

Nifedipine
Potassium
Induced Heart Arrest
Hypothermia
Ventricular Function
Reperfusion
Felidae
Recovery of Function
Calcium Channel Blockers
Ventricular Pressure
Heart Arrest
Carbon Dioxide
Mass Spectrometry
Ischemia
Oxygen
Control Groups

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine

Cite this

Magee, P. G., Flaherty, J. T., Bixler, T. J., Glower, D., Gardner, T. J., Bukley, B. H., & Gott, V. L. (1979). Comparison of myocardial protection with nifedipine and potassium. Circulation, 60(2 II).

Comparison of myocardial protection with nifedipine and potassium. / Magee, P. G.; Flaherty, J. T.; Bixler, T. J.; Glower, D.; Gardner, T. J.; Bukley, B. H.; Gott, Vincent L.

In: Circulation, Vol. 60, No. 2 II, 1979.

Research output: Contribution to journalArticle

Magee, PG, Flaherty, JT, Bixler, TJ, Glower, D, Gardner, TJ, Bukley, BH & Gott, VL 1979, 'Comparison of myocardial protection with nifedipine and potassium', Circulation, vol. 60, no. 2 II.
Magee PG, Flaherty JT, Bixler TJ, Glower D, Gardner TJ, Bukley BH et al. Comparison of myocardial protection with nifedipine and potassium. Circulation. 1979;60(2 II).
Magee, P. G. ; Flaherty, J. T. ; Bixler, T. J. ; Glower, D. ; Gardner, T. J. ; Bukley, B. H. ; Gott, Vincent L. / Comparison of myocardial protection with nifedipine and potassium. In: Circulation. 1979 ; Vol. 60, No. 2 II.
@article{cf04ff6046684e28bd2bee4124cab3b2,
title = "Comparison of myocardial protection with nifedipine and potassium",
abstract = "Nifedipine, a slow-channel calcium blocker, is thought to provide useful myocardial protection during prolonged total ischemia and reperfusion. An isolated, isovolumic, feline heart model was used to assess the effectiveness of nifedipine in both cardioplegic (100 μg/10 ml) and noncardioplegic (10 μg/10 ml) doses for providing myocardial preservation during 90 minutes of hyperthermic ischemic arrest and 45 minutes of normothermic reperfusion. Use of nifedipine was compared to hypothermia (27°C) alone and to hypothermia with potassium cardioplegia. Ventricular function was assessed by recovery of isovolumic left ventricular developed pressure and dP/dt. Myocardial carbon dioxide tension (PCO2) and myocardial oxygen tension (PO2) were measured by mass spectrometry. Potassium cardioplegia and the higher dose of nifedipine resulted in immediate asystole. The rates of rise of PCO2 were greatest in the group receiving 10 μg nifedipine and in the control group. The rates of rise in the two cardioplegic groups were significantly lower. Recovery of ventricular function was significantly lower with low-dose nifedipine than with potassium cardioplegia. Higher dose nifedipine resulted in a return of function, which was no different than with potassium cardioplegia. Morphologic protection was better with higher dose nifedipine and potassium cardioplegia than with either low-dose cardioplegia or hypothermia alone. These results demonstrate that nifedipine in a cardioplegic dose results in preservation of myocardial structure and function that is similar to that obtained with potassium cardioplegia. In lower noncardioplegic dose, nifedipine does not appear to offer additional protection compared to hypothermia alone. Whether persistent depression of ventricular contractility will limit nifedipine's clinical usefulness as a myocardial protection agent will require further study.",
author = "Magee, {P. G.} and Flaherty, {J. T.} and Bixler, {T. J.} and D. Glower and Gardner, {T. J.} and Bukley, {B. H.} and Gott, {Vincent L}",
year = "1979",
language = "English (US)",
volume = "60",
journal = "Circulation",
issn = "0009-7322",
publisher = "Lippincott Williams and Wilkins",
number = "2 II",

}

TY - JOUR

T1 - Comparison of myocardial protection with nifedipine and potassium

AU - Magee, P. G.

AU - Flaherty, J. T.

AU - Bixler, T. J.

AU - Glower, D.

AU - Gardner, T. J.

AU - Bukley, B. H.

AU - Gott, Vincent L

PY - 1979

Y1 - 1979

N2 - Nifedipine, a slow-channel calcium blocker, is thought to provide useful myocardial protection during prolonged total ischemia and reperfusion. An isolated, isovolumic, feline heart model was used to assess the effectiveness of nifedipine in both cardioplegic (100 μg/10 ml) and noncardioplegic (10 μg/10 ml) doses for providing myocardial preservation during 90 minutes of hyperthermic ischemic arrest and 45 minutes of normothermic reperfusion. Use of nifedipine was compared to hypothermia (27°C) alone and to hypothermia with potassium cardioplegia. Ventricular function was assessed by recovery of isovolumic left ventricular developed pressure and dP/dt. Myocardial carbon dioxide tension (PCO2) and myocardial oxygen tension (PO2) were measured by mass spectrometry. Potassium cardioplegia and the higher dose of nifedipine resulted in immediate asystole. The rates of rise of PCO2 were greatest in the group receiving 10 μg nifedipine and in the control group. The rates of rise in the two cardioplegic groups were significantly lower. Recovery of ventricular function was significantly lower with low-dose nifedipine than with potassium cardioplegia. Higher dose nifedipine resulted in a return of function, which was no different than with potassium cardioplegia. Morphologic protection was better with higher dose nifedipine and potassium cardioplegia than with either low-dose cardioplegia or hypothermia alone. These results demonstrate that nifedipine in a cardioplegic dose results in preservation of myocardial structure and function that is similar to that obtained with potassium cardioplegia. In lower noncardioplegic dose, nifedipine does not appear to offer additional protection compared to hypothermia alone. Whether persistent depression of ventricular contractility will limit nifedipine's clinical usefulness as a myocardial protection agent will require further study.

AB - Nifedipine, a slow-channel calcium blocker, is thought to provide useful myocardial protection during prolonged total ischemia and reperfusion. An isolated, isovolumic, feline heart model was used to assess the effectiveness of nifedipine in both cardioplegic (100 μg/10 ml) and noncardioplegic (10 μg/10 ml) doses for providing myocardial preservation during 90 minutes of hyperthermic ischemic arrest and 45 minutes of normothermic reperfusion. Use of nifedipine was compared to hypothermia (27°C) alone and to hypothermia with potassium cardioplegia. Ventricular function was assessed by recovery of isovolumic left ventricular developed pressure and dP/dt. Myocardial carbon dioxide tension (PCO2) and myocardial oxygen tension (PO2) were measured by mass spectrometry. Potassium cardioplegia and the higher dose of nifedipine resulted in immediate asystole. The rates of rise of PCO2 were greatest in the group receiving 10 μg nifedipine and in the control group. The rates of rise in the two cardioplegic groups were significantly lower. Recovery of ventricular function was significantly lower with low-dose nifedipine than with potassium cardioplegia. Higher dose nifedipine resulted in a return of function, which was no different than with potassium cardioplegia. Morphologic protection was better with higher dose nifedipine and potassium cardioplegia than with either low-dose cardioplegia or hypothermia alone. These results demonstrate that nifedipine in a cardioplegic dose results in preservation of myocardial structure and function that is similar to that obtained with potassium cardioplegia. In lower noncardioplegic dose, nifedipine does not appear to offer additional protection compared to hypothermia alone. Whether persistent depression of ventricular contractility will limit nifedipine's clinical usefulness as a myocardial protection agent will require further study.

UR - http://www.scopus.com/inward/record.url?scp=0018750508&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0018750508&partnerID=8YFLogxK

M3 - Article

VL - 60

JO - Circulation

JF - Circulation

SN - 0009-7322

IS - 2 II

ER -