Assessment of the effectiveness of descending aortomyoplasty for nonischemic cardiac failure by means of the subendocardial viability index.
BACKGROUND
Paraaortic or external aortic counterpulsation is been investigated as a definitive ventricular assistance in cases of terminal congestive heart failure and when heart transplantation is counterindicated. Our aims is to assess the haemodynamic effects of an descending aortomyoplasty in a biological model of congestive heart failure.


METHODS
As specimens, we used 10 "Large White" pigs. Mean weight was 25,3+/-2,14 Kg. After the administration of conventional anaesthesia, dissection of the latissimus dorsi muscle was performed. Then we performed a thoracotomy at the level of the fourth intercostal space to reach the thoracic aorta. The aorta is dissected 7 centimetres from the output of the subclavia artery and it is wrapped by the dissected muscle. A cardiomyostimulator is provided in order to allow the synchronization between the diastole and the muscle contraction. The model of heart failure was provoked using Verapamil plus Propanolol i.v.


RESULTS
A significant increase of the systolic and diastolic aortic pressure (54,2+/-4,05 and 27.5+/-6.77 mmHg versus 76.5+/-6.25 and 56.4+/-5.2 mmHg, p<0,001) and a significant decrease of the left ventricle telediastolic pressures were observed (12.9+/-9 versus 2.6+/-1.57 mmHg, p<0,001). An increase of the cardiac output (0.363+/-0.11 versus 0.846+/-0.08 L/min, p<0,001) and the Subendocardial Viability Index (0.968+/-0.076 versus 1.351+/-0,107, p<0,001)were observed in a model of non-ischemic heart failure.


CONCLUSIONS
Descending Aortomyoplasty as a technique to support circulation in cases of acute heart failure, improves the parameters of ventricular function, aiding the functional recovery of the left ventricle and improving significantly cardiac output as well as diastolic and systolic cardiac pressure. In addition to this, improves the Subendocardial Viability Index in cases of acute heart failure, which indirectly reflects an improvement of the Transmural and Subendocardial Perfusion of the failing heart.
Ordoñez
A
A
Cardiovascular Surgery and Cardiac Transplantation Service, University Hospital Virgen del Ricio, Seville, Spain.
Hernández
A
A
Domínguez
J M
JM
Carretero
E G
EG
Rodriguez
M F
MF
Peñas
M M
MM
Sánchez
E C
EC
Ruiz
M R
MR
D000818:Animals; D001013:Aorta, Thoracic / Q000503:physiopathology / Q000601:surgery; D002302:Cardiac Output / Q000502:physiology; D018421:Cardiomyoplasty; D003326:Coronary Circulation / Q000502:physiology*; D004195:Disease Models, Animal; D006333:Heart Failure / Q000503:physiopathology* / Q000601:surgery*; D013552:Swine; D016896:Treatment Outcome; D016276:Ventricular Function / Q000502:physiology; D017725:Ventricular Pressure / Q000502:physiology