Disuse inhibition of newly functional coronary collateral circulation in ponies

1992 ◽  
Vol 262 (2) ◽  
pp. H385-H390
Author(s):  
K. S. Rugh ◽  
C. R. Ross ◽  
R. D. Sarazan ◽  
R. B. Boatwright ◽  
D. O. Williams ◽  
...  
Keyword(s):  
Diastolic Pressure ◽  
Left Ventricular ◽  
Stroke Work ◽  
Shortening Velocity ◽  
Coronary Collateral ◽  
Work Index ◽  
Percent Recovery ◽  
Velocity Of Shortening ◽  
Stroke Work Index ◽  
Long Time

We evaluated the loss of coronary collateral function in the absence of stimulation (disuse inhibition) by doubling the interval between successive left anterior descending coronary artery (LAD) occlusions in ponies in which collateral function initially had been enhanced by 2-min occlusions at 30-min intervals. Before collateralization, occlusion caused segment systolic shortening, velocity of shortening, and stroke work index in the LAD-dependent left ventricular apex to decrease, whereas heart rate and left ventricular end-diastolic pressure increased. After 476 +/- 102 occlusions, segment function recovered to preocclusion levels and hemodynamics were unchanged during occlusion. Occlusion did not elicit sustained functional deterioration until the occlusion interval was greater than or equal to 32 h. During the occlusion after the 128-h interval, segment systolic shortening, velocity of shortening, and stroke work index were reduced 69 +/- 8, 38 +/- 9, and 46 +/- 13%, respectively. Percent recovery of systolic shortening during successive occlusions declined exponentially (T1/e = 102.0 +/- 17.3 h). Thus, in ponies collateral function progressively declines when the occlusion interval is greater than or equal to 32 h, but complete inhibition does not occur even after 128 h without occlusion. This indicates that collateral function in ponies can be maintained by occlusions that are far less frequent than those needed for initial collateral development. The long time constant of collateral disuse inhibition suggests that equine collaterals are quite resistant to the effects of occlusion cessation and differ from canine collaterals in that respect.

Sweating, hemodynamic responses, and thermal equilibration during hyperthermia in humans

1987 ◽  
Vol 62 (4) ◽  
pp. 1596-1602 ◽  
Author(s):  
A. S. Tonnesen ◽  
C. Marnock ◽  
J. M. Bull ◽  
C. J. Morgenweck ◽  
K. D. Fallon
Keyword(s):  
Heart Rate ◽  
Heat Stress ◽  
Venous Pressure ◽  
Left Ventricular ◽  
Volume Index ◽  
Stroke Work ◽  
Work Index ◽  
Stroke Work Index ◽  
Ventricular Stroke Work Index ◽  
Pulmonary Arterial

Hyperthermia, to 42 degrees C, for treatment of cancer, was induced 23 times in 13 anesthetized patients utilizing an extracorporeal heat-exchange circuit. Sweating rate over the chest, abdomen, arm and forearm ranged from 0.2 to 0.9 mg sweat X min-1 X cm-2. Cardiac index (CI), stroke volume index (SVI), left ventricular stroke work index, and right ventricular stroke work index initially increased to 221 +/- 12.5, 162 +/- 9.6, 142 +/- 11, and 203 +/- 29% but later fell to 169–173, 113–120, 69, and 148–117% of control, respectively. Heart rate initially rose to 145 +/- 5.9% and then stabilized at 160–162% of control. Pulmonary arterial occlusion pressure and central venous pressure initially fell to 82 +/- 8 and 93 +/- 9% but later rose to 87–102 and 105–120% of control levels, respectively. The hemodynamic response to severe heat stress in anesthetized humans was characterized by peripheral vasodilation accompanied by compensatory increases in heart rate and CI. Ventricular function, as reflected by SVI and CI, declined with continued heat stress, despite reduced afterload and stable or increased filling pressures. Pulmonary arterial temperature rose fastest, followed by the esophageal, rectal, and bladder temperatures, respectively. Jugular bulb temperature also rose rapidly.

scholarly journals Noninvasive Echocardiographic Left Ventricular Stroke Work Index Predicts Mortality in Cardiac Intensive Care Unit Patients

2020 ◽  
Vol 13 (11) ◽  
Author(s):  
Jacob C. Jentzer ◽  
Nandan S. Anavekar ◽  
Barry J. Burstein ◽  
Barry A. Borlaug ◽  
Jae K. Oh
Keyword(s):  
Hospital Mortality ◽  
Transthoracic Echocardiography ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Stroke Work ◽  
Ventricular Ejection Fraction ◽  
Work Index ◽  
Stroke Work Index ◽  
Ventricular Stroke Work Index ◽  
Cardiac Intensive Care

Background: Reduced left ventricular stroke work index (LVSWI) has been associated with adverse outcomes in several populations of patients with chronic heart disease, but no prior studies have examined this metric in cardiac intensive care unit (CICU) patients. We sought to determine whether a low LVSWI, as measured noninvasively using transthoracic echocardiography, is associated with higher mortality in CICU patients. Methods: Using a database of unique Mayo Clinic CICU admissions from 2007 to 2018, we identified patients with LVSWI measured by transthoracic echocardiography within 1 day of CICU admission. Hospital mortality was analyzed using multivariable logistic regression, and 1-year mortality was analyzed using multivariable Cox proportional-hazards analysis, adjusted for left ventricular ejection fraction and known predictors of hospital mortality. Results: We included 4536 patients with a mean age of 68±14 years (36% women). Admission diagnoses (not mutually exclusive) included acute coronary syndrome in 62%, heart failure in 46%, and cardiogenic shock in 11%. The mean LVSWI was 38±14 g×min/m 2 , and in-hospital mortality occurred in 6% of patients. LVSWI had better discrimination for hospital mortality than left ventricular ejection fraction ( P <0.001 by De Long test). Higher LVSWI was associated with lower in-hospital mortality (adjusted odds ratio, 0.72 per 10 g×min/m 2 higher [95% CI, 0.61–0.84]; P <0.001) and lower 1-year mortality (adjusted hazard ratio, 0.812 per 1 g×min/m 2 higher [95% CI, 0.759–0.868]; P <0.001). Stepwise decreases in hospital and 1-year mortality were observed with higher LVSWI. Conclusions: Low LVSWI, reflecting poor left ventricular systolic and diastolic performance, is associated with increased short-term and long-term mortality among CICU patients. This emphasizes the importance of Doppler transthoracic echocardiography as a predictor of outcomes among critically ill patients. Further study is required to determine whether early interventions to optimize LVSWI can improve outcomes in the CICU setting.

Prognostic Importance of Pulmonary Artery Pulsatility Index and Right Ventricular Stroke Work Index in End-Stage Heart Failure Patients

Cardiology ◽  
2022 ◽  
Author(s):  
Zubeyde Bayram ◽  
Cem Dogan ◽  
Suleyman Cagan Efe ◽  
Ali Karagoz ◽  
Busra Guvendi ◽  
...  
Keyword(s):  
Right Ventricular ◽  
Left Ventricular ◽  
Stroke Work ◽  
Work Index ◽  
J Curve ◽  
Stroke Work Index ◽  
Ventricular Stroke Work Index ◽  
End Stage Heart Failure ◽  
End Stage ◽  
Right Ventricular Stroke Work

Background: Right ventricular (RV) failure is an important cause of morbidity and mortality in patients with left ventricular (LV) end-stage heart failure (ESHF). Pulmonary artery pulsatility index (PAPi) and right ventricular stroke work index (RVSWI) are invasive parameters related to RV function. This study aimed to investigate the prognostic impact of PAPi and RVSWI in these patients. Methods and Results: In this study, 416 patients with ESHF were included. The adverse cardiac event (ACE) was defined as left ventricular assist device (LVAD) implantation, urgent heart transplantation, or cardiac mortality. There were 218 ACE cases and 198 non-ACE cases over a median follow-up of 503.50 days. Patients with ACE had lower PAPi and similar RVSWI compared to those without ACE (3.1±1.9 vs. 3.7±2.3, P=0.003 and 7.3±4.9 vs. 6.9±4.4, P=0.422, respectively). According to the results of multivariate analysis, while PAPi (from 2 to 5.65) was associated with ACE, RVSWI (from 3.62 to 9.75) was not associated with ACE (HR: 0.75, 95% CI (0.55-0.95), P=0.031; HR: 0.79, 95% CI: (0.58-1.09), P=0.081, , respectively). Survival analysis revealed that PAPi ≤2.56 was associated with a higher ACE risk compared to PAPi >2.56 (HR: 1.46, 95% CI: 1.11-1.92, P=0.006). PAPi ≤2.56 could predict ACE with 56.7% sensitivity and 51.3% specificity at one year. Furthermore, the association between RVSWI and ACE was nonlinear (J-curve pattern). Low and high values seem to be associated with higher ACE risk compared to intermediate values. Conclusion: The low PAPi was an independent risk for ACE and it had a linear association with it. However, RVSWI seems to be have a nonlinear association with ACE (J-curve pattern).

Melagatran, a Low Molecular Weight Thrombin Inhibitor, Counteracts Endotoxin-induced Haemodynamic and Renal Dysfunctions in the Pig

1998 ◽  
Vol 80 (12) ◽  
pp. 1022-1026 ◽  
Author(s):  
Anders Larsson ◽  
Tom Saldeen ◽  
Christer Mattsson ◽  
Mats Eriksson
Keyword(s):  
Molecular Weight ◽  
Septic Shock ◽  
Resistance Index ◽  
Left Ventricular ◽  
Thrombin Inhibitor ◽  
Low Molecular Weight ◽  
Stroke Work ◽  
Work Index ◽  
Stroke Work Index ◽  
Ventricular Stroke Work Index

SummaryCoagulation and fibrinolysis are crucial in septic shock and inhibition of thrombin may be beneficial in this circumstance. Since porcine endotoxaemia has been found to replicate severe septic shock, a low molecular weight thrombin inhibitor, melagatran, was infused during the first 3 out of 6 h of endotoxaemia in pigs. Plasma creatinine (p <0.01) and urinary output (p <0.05) were less affected in the melagatran + endotoxin group (n = 6) as compared to endotoxaemic controls (n = 9). The left ventricular stroke work index, systemic vascular resistance index and oxygen extraction were all less affected (p <0.05) by endotoxin during the infusion of melagatran. The plasma concentration of melagatran declined with an apparent plasma half-life of 5 h as soon as the infusion was stopped. APTT, however, continued to increase after the infusion of melagatran had stopped and reached a maximum of 113 s at 5 h (baseline 17 s). APTT in endotoxaemic control pigs reached a maximum of 22 s. Thus, melagatran may counteract some consequences of endotoxaemia.

Calculation of the Left Ventricular Stroke Work Index

1993 ◽  
Vol 21 (8) ◽  
pp. 1248 ◽  
Author(s):  
Günter Pilz ◽  
Roland Appel ◽  
Paul McGinn
Keyword(s):  
Left Ventricular ◽  
Stroke Work ◽  
Work Index ◽  
Stroke Work Index ◽  
Ventricular Stroke Work Index
Sign in / Sign up

Export Citation Format

Share Document