Ischemic cardiomyopathy in pigs with two-vessel  occlusion and viable, chronically dysfunctional myocardium

A chronic left anterior descending coronary artery (LAD) stenosis leads to the development of hibernating myocardium with severe regional hypokinesis but normal global ventricular function after 3 mo. We hypothesized that two-vessel occlusion would accelerate the progression to hibernating myocardium and lead to global left ventricular (LV) dysfunction and heart failure. Pigs were instrumented with a fixed 1.5-mm constrictor on the proximal LAD and circumflex arteries. After 2 mo, there were no overt signs of right-heart failure and triphenyl tetrazolium chloride infarction was trivial (1.4 ± 0.1% of the LV). Compared with shams, regional function [myocardial systolic excursion (ΔWT); 2.1 ± 0.3 vs. 4.6 ± 0.4 mm, P < 0.05] and resting perfusion (0.90 ± 0.13 vs. 1.32 ± 0.09 ml · min−1 · g−1, P < 0.05) were reduced, consistent with hibernating myocardium. Pulmonary systolic (45.9 ± 3.3 vs. 36.5 ± 2.2 mmHg, P < 0.05) and wedge pressures (19.1 ± 1.6 vs. 11.2 ± 0.9 mmHg, P < 0.05) were increased with global ventricular dysfunction (ejection fraction 43 ± 2 vs. 50 ± 2%, P < 0.05). Early LV remodeling was present with increased cavity size and mass. Reductions in sarcoplasmic reticulum Ca2+-ATPase and phospholamban were confined to the dysfunctional LAD region with no change in calsequestrin. Thus combined stenoses of the LAD and circumflex arteries accelerate the development of hibernating myocardium and result in compensated heart failure.

Download Full-text

Heart failure progression is accelerated following myocardial infarction in type 2 diabetic rats

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01338.2006 ◽

2007 ◽

Vol 293 (3) ◽

pp. H1609-H1616 ◽

Cited By ~ 20

Author(s):

Margaret P. Chandler ◽

Eric E. Morgan ◽

Tracy A. McElfresh ◽

Theodore A. Kung ◽

Julie H. Rennison ◽

...

Keyword(s):

Myocardial Infarction ◽

Heart Failure ◽

Left Ventricular ◽

Coronary Artery Ligation ◽

Contractile Dysfunction ◽

Lv Dysfunction ◽

Lv Remodeling ◽

Heart Failure Progression ◽

Type 2 Diabetic

Clinical studies have shown a greater incidence of myocardial infarction in diabetic patients, and following an infarction, diabetes is associated with an increased risk for the development of left ventricular (LV) dysfunction and heart failure. The goal of this study was to determine if the progression of heart failure following myocardial infarction in type 2 diabetic (T2D) rats is accelerated compared with nondiabetic rats. Male nondiabetic Wistar-Kyoto (WKY) and T2D Goto-Kakizaki (GK) rats underwent coronary artery ligation or sham surgery to induce heart failure. Postligation (8 and 20 wk), two-dimensional echocardiography and LV pressure measurements were made. Heart failure progression, as assessed by enhanced LV remodeling and contractile dysfunction, was accelerated 8 wk postligation in the T2D animals. LV remodeling was evident from increased end-diastolic and end-systolic diameters and areas in the GK compared with the WKY infarcted group. Furthermore, enhanced LV contractile dysfunction was evident from a greater deterioration in fractional shortening and enhanced myocardial performance index (an index of global LV dysfunction) in the GK infarcted group. This accelerated progression was accompanied by greater increases in atrial natriuretic factor and skeletal α-actin (gene markers of heart failure and hypertrophy) mRNA levels in GK infarcted hearts. Despite similar decreases in metabolic gene expression (i.e., peroxisome proliferator-activated receptor-α-regulated genes associated with fatty acid oxidation) between infarcted WKY and GK rat hearts, myocardial triglyceride levels were elevated in the GK hearts only. These results, demonstrating enhanced remodeling and LV dysfunction 8 wk postligation provide evidence of an accelerated progression of heart failure in T2D rats.

Download Full-text

Right ventricular dysfunction and pulmonary hypertension: a neglected presentation of thyrotoxicosis

Endocrinology Diabetes and Metabolism Case Reports ◽

10.1530/edm-18-0012 ◽

2018 ◽

Vol 2018 ◽

Cited By ~ 2

Author(s):

Carolina Shalini Singarayar ◽

Foo Siew Hui ◽

Nicholas Cheong ◽

Goay Swee En

Keyword(s):

Heart Failure ◽

Pulmonary Hypertension ◽

Right Ventricular ◽

Left Ventricular Dysfunction ◽

Ventricular Dysfunction ◽

Right Ventricular Dysfunction ◽

Right Heart Failure ◽

Left Ventricular ◽

Newly Diagnosed ◽

Right Heart

Summary Thyrotoxicosis is associated with cardiac dysfunction; more commonly, left ventricular dysfunction. However, in recent years, there have been more cases reported on right ventricular dysfunction, often associated with pulmonary hypertension in patients with thyrotoxicosis. Three cases of thyrotoxicosis associated with right ventricular dysfunction were presented. A total of 25 other cases of thyrotoxicosis associated with right ventricular dysfunction published from 1994 to 2017 were reviewed along with the present 3 cases. The mean age was 45 years. Most (82%) of the cases were newly diagnosed thyrotoxicosis. There was a preponderance of female gender (71%) and Graves’ disease (86%) as the underlying aetiology. Common presenting features included dyspnoea, fatigue and ankle oedema. Atrial fibrillation was reported in 50% of the cases. The echocardiography for almost all cases revealed dilated right atrial and or ventricular chambers with elevated pulmonary artery pressure. The abnormal echocardiographic parameters were resolved in most cases after rendering the patients euthyroid. Right ventricular dysfunction and pulmonary hypertension are not well-recognized complications of thyrotoxicosis. They are life-threatening conditions that can be reversed with early recognition and treatment of thyrotoxicosis. Signs and symptoms of right ventricular dysfunction should be sought in all patients with newly diagnosed thyrotoxicosis, and prompt restoration of euthyroidism is warranted in affected patients before the development of overt right heart failure. Learning points: Thyrotoxicosis is associated with right ventricular dysfunction and pulmonary hypertension apart from left ventricular dysfunction described in typical thyrotoxic cardiomyopathy. Symptoms and signs of right ventricular dysfunction and pulmonary hypertension should be sought in all patients with newly diagnosed thyrotoxicosis. Thyrotoxicosis should be considered in all cases of right ventricular dysfunction or pulmonary hypertension not readily explained by other causes. Prompt restoration of euthyroidism is warranted in patients with thyrotoxicosis complicated by right ventricular dysfunction with or without pulmonary hypertension to allow timely resolution of the abnormal cardiac parameters before development of overt right heart failure.

Download Full-text

Review Article: Management of Perioperative Anesthesia in Right Heart Failure

Folia Medica Indonesiana ◽

10.20473/fmi.v54i1.8056 ◽

2018 ◽

Vol 54 (1) ◽

pp. 75

Author(s):

Fajar Perdhana ◽

Herdono Purnomo

Keyword(s):

Heart Failure ◽

Cardiac Surgery ◽

Right Ventricular ◽

Ventricular Dysfunction ◽

Right Ventricular Dysfunction ◽

Right Heart Failure ◽

Left Ventricular ◽

Right Ventricular Failure ◽

Ventricular Failure ◽

Right Heart

Right ventricular dysfunction and failure receive much less attention than the left ventricular failure. Right ventricular dysfunction or failure is associated with increased mortality rates in cardiac surgery, surgical cases other than cardiac surgery and also in patients treated in the ICU. The purpose of this article review was to describe the anatomy, physiology and pathophysiology of right ventricular failure, its detection and diagnosis, and management considerations from anesthetic point of view, including preoperative, intraoperative and postoperative stages. Cardiac surgery may result in right ventricular failure. For example, 0.1% post cardiotomy patients experience severe right heart failure and require long-term inotropic support, and so do 2-3% of post-transplant patients, and 20-30% of patients installed with instrument in his left heart. Therefore, anesthesiologists play a major role in perioperative and postoperative intensive care and are obliged to comprehend the nature of right ventricular dysfunction and failure so as to carry out early detection, prevent and manage patients with right ventricular dysfunction.

Download Full-text

Prognostic Implications of Asymptomatic Left Ventricular Dysfunction in Patients Undergoing Vascular Surgery

Anesthesiology ◽

10.1097/aln.0b013e3181da89ca ◽

2010 ◽

Vol 112 (6) ◽

pp. 1316-1324 ◽

Cited By ~ 90

Author(s):

Willem-Jan Flu ◽

Jan-Peter van Kuijk ◽

Sanne E. Hoeks ◽

Ruud Kuiper ◽

Olaf Schouten ◽

...

Keyword(s):

Heart Failure ◽

Vascular Surgery ◽

Cardiovascular Mortality ◽

Cardiovascular Events ◽

Ventricular Dysfunction ◽

Left Ventricular ◽

Lv Dysfunction ◽

Mortality Hazard ◽

Prognostic Implications

Background The prognostic value of heart failure symptoms on postoperative outcome is well acknowledged in perioperative guidelines. The prognostic value of asymptomatic left ventricular (LV) dysfunction remains unknown. This study evaluated the prognostic implications of asymptomatic LV dysfunction in vascular surgery patients assessed with routine echocardiography. Methods Echocardiography was performed preoperatively in 1,005 consecutive vascular surgery patients. Systolic LV dysfunction was defined as LV ejection fraction less than 50%. Ratio of mitral-peak velocity during early and late filling, pulmonary vein flow, and deceleration time was used to diagnose diastolic LV dysfunction. Troponin-T measurements and electrocardiograms were performed routinely perioperatively. Multivariate regression analyses evaluated the relation between LV function and the study endpoints, 30-day cardiovascular events, and long-term cardiovascular mortality. Results Left ventricular dysfunction was diagnosed in 506 (50%) patients of which 80% were asymptomatic. In open vascular surgery (n = 649), both asymptomatic systolic and isolated diastolic LV dysfunctions were associated with 30-day cardiovascular events (odds ratios 2.3, 95% confidence interval [CI] 1.4-3.6 and 1.8, 95% CI 1.1-2.9, respectively) and long-term cardiovascular mortality (hazard ratios 4.6, 95% CI 2.4-8.5 and 3.0, 95% CI 1.5-6.0, respectively). In endovascular surgery (n = 356), only symptomatic heart failure was associated with 30-day cardiovascular events (odds ratio 1.8, 95% CI 1.1-2.9) and long-term cardiovascular mortality (hazard ratio 10.3, 95% CI 5.4-19.3). Conclusions This study demonstrated that asymptomatic LV dysfunction is predictive for 30-day and long-term cardiovascular outcome in open vascular surgery patients. These data suggest that preoperative risk stratification should include not only solely heart failure symptoms but also routine preoperative echocardiography to risk stratify open vascular surgery patients.

Download Full-text