Extent of utilization of the Frank-Starling mechanism in conscious dogs

1978 ◽  
Vol 234 (4) ◽  
pp. H338-H345 ◽  
Author(s):  
D. H. Boettcher ◽  
S. F. Vatner ◽  
G. R. Heyndrickx ◽  
E. Braunwald
Keyword(s):  
Coronary Artery ◽  
Myocardial Ischemia ◽  
Volume Expansion ◽  
Left Main Coronary Artery ◽  
Left Ventricular ◽  
Conscious Dogs ◽  
Left Main ◽  
Volume Loading ◽  
Conscious Animal ◽  
Controlling Mechanism

The extent to which an increase in preload increases left ventricular (LV) end-diastolic (ED) diameter (D) was studied in seven conscious dogs instrumented with ultrasonic D transducers and miniature LV pressure (P) gauges. Preload was elevated by three techniques: 1) volume loading with saline infusion, 2) induction of global myocardial ischemia by constricting the left main coronary artery, and 3) infusion of methoxamine. These three interventions increased LVEDP to over 30 mmHg from a control of 10 +/- 1 mmHg. With volume loading, LVEDD rose by only 1.55 +/- 0.39 mm from a control of 44.08 +/- 1.08 mm; with ischemia LVEDD rose by only .96 +/- .29 mm from a control of 42.55 +/- 2.18 mm, while with methoxamine LVEDD rose by only 1.34 +/- 0.38 mm from a control of 43.89 +/- 2.07 mm. In contrast, in the open-chest, anesthetized dog, LVEDD was greatly reduced and volume expansion resulted in a profound increase in LVEDD. Thus, the Frank-Starling mechanism is not an important controlling mechanism in the normal, reclining, conscious animal, since LVEDD appears to be near maximal at rest and does not increase substantially despite striking increases in LVEDP.

scholarly journals Successful interdisciplinary treatment as a rare cause of acute myocardial ischemia by intermittent tumor-associated obstruction of the left main coronary artery– A case report

2021 ◽  
Author(s):  
Katharina Huenges ◽  
Franz Hartmann ◽  
Bernd Panholzer ◽  
Thomas Puehler
Keyword(s):  
Case Report ◽  
Coronary Artery ◽  
Aortic Valve ◽  
Myocardial Ischemia ◽  
Left Main Coronary Artery ◽  
Left Ventricular ◽  
Papillary Fibroelastoma ◽  
Interdisciplinary Treatment ◽  
Bridge To Surgery ◽  
Left Main

Abstract Background A papillary fibroelastoma of the aortic valve has been reported as a rare cause of myocardial ischemia. An advanced combined interventional and surgical approach leading to sufficient therapy for the patient is presented in this case report. Case summary A 56-year old female patient presented in an emergency room of a hospital with an acute coronary syndrome. Over 1.5 years, recurrent stable angina had been known in the patient and significant coronary artery disease has already been ruled out in a previous coronary angiogram. The patient was immediately transferred to the catheter laboratory due to cardiogenic shock where a drug-eluting stent was implanted to, firstly, recanalize the left main coronary artery and, secondly, to protect the left main ostium from obstruction by an echocardiographic-proven mass. During subsequent deterioration of hemodynamics caused by decreasing left ventricular function and acute severe mitral insufficiency, firstly an intra-aortic balloon pump and secondly a VA-ECMO was established through the femoral vessels. The patient was transferred to our cardiac surgery unit and was successfully operated utilizing a valve-sparing technique by extracting the tumor mass from the left coronary cusp and extracting the stent carefully from the left main coronary artery. Histology revealed a papillary fibroelastoma (Figure 4). Conclusion A papillary fibroelastoma of the aortic valve with intermittent obstruction of the coronary arteries requires surgical therapy. Interventional recanalization and extracorporeal support might be useful strategies to ensure the patient’s safety as a bridge to surgery.

Coronary artery z score values in adolescent elite male soccer players

2020 ◽  
pp. 1-5
Author(s):  
Stephan Gerling ◽  
Tobias Pollinger ◽  
Markus Johann Dechant ◽  
Michael Melter ◽  
Werner Krutsch ◽  
...  
Keyword(s):  
Coronary Artery ◽  
Coronary Arteries ◽  
High Intensity ◽  
Left Main Coronary Artery ◽  
Left Ventricular ◽  
Soccer Players ◽  
Z Score ◽  
Left Main ◽  
Luminal Diameter ◽  
The Mean

Abstract Background: With the increased training loads at very early ages in European elite youth soccer, there is an interest to analyse coronary artery remodelling due to high-intensity exercise. Design and methods: Prospective echocardiographic study in 259 adolescent elite male soccer players and 48 matched controls. Results: The mean age was 12.7 ± 0.63 years in soccer players and 12.6 ± 0.7 years in controls (p > 0.05). Soccer players had significant greater indexed left ventricular mass (93 ± 13 g/m2 versus 79 ± 12 g/m2, p = 0.001). Both coronary arteries origin could be identified in every participant. In soccer players, the mean diameter of the left main coronary artery was 3.67 mm (SD ± 0.59) and 2.61 mm (SD ± 0.48) for right main coronary artery. Controls showed smaller mean luminal diameter (left main coronary artery, p = 0.01; right main coronary artery, p = 0.025). In soccer players, a total of 91% (n = 196) and in controls a total of 94% (n = 45) showed left main coronary artery z scores within the normal range: −2.0 to 2.0. In right main coronary artery, a pattern of z score values distribution was comparable (soccer players 94%, n = 202 vs. controls 84%, n = 40). A subgroup of soccer players had supernormal z score values (>2.0 to 2.5) for left main coronary artery (9%, n = 19, p = 0.01) and right main coronary artery (6%, n = 10, p = 0.025), respectively. Conclusion: Elite soccer training in early adolescence may be a stimulus strong enough to develop increased coronary arteries diameters. In soccer players, a coronary artery z score >2.0–2.5 might reflect a physiologic response induced by multiannual high-intensity training.

scholarly journals Left anterior descending coronary artery dissection during ventricular tachycardia ablation – case report

2018 ◽  
Vol 56 (1) ◽  
pp. 63-66
Author(s):  
Kresimir Kordic ◽  
Sime Manola ◽  
Ivan Zeljkovic ◽  
Ivica Benko ◽  
Nikola Pavlovic
Keyword(s):  
Ventricular Tachycardia ◽  
Coronary Artery ◽  
Left Main Coronary Artery ◽  
Left Ventricular ◽  
Artery Dissection ◽  
Complication Rates ◽  
Left Main ◽  
Coronary Artery Dissection ◽  
Ventricular Tachycardia Ablation ◽  
First Case

Abstract Fascicular left ventricular tachycardia (VT) is the second most frequent idiopathic left VT in the setting of a structurally normal heart. Catheter ablation is curative in most patients with low complication rates. We report a case of ostial left anterior descending coronary artery (LAD) occlusion during fascicular ventricular tachycardia ablation. Dissection was the most likely cause of LAD obstruction. To the authors’ best knowledge, this is the first case reporting selective LAD dissection during electrophysiology study with no left main coronary artery (LMCA) affection.

Left main coronary artery atresia in an infant with Shone’s complex

2016 ◽  
Vol 26 (5) ◽  
pp. 991-992 ◽  
Author(s):  
Matthew F. Pizzuto ◽  
Jeffrey D. Zampi
Keyword(s):  
Coronary Artery ◽  
Left Ventricular Function ◽  
Ventricular Function ◽  
Left Main Coronary Artery ◽  
Left Ventricular ◽  
Subaortic Stenosis ◽  
Left Main ◽  
Rare Finding ◽  
Depressed Left Ventricular Function

AbstractA 6-month-old infant with Shone’s complex was found to have left main coronary artery atresia during evaluation for recurrent subaortic stenosis with depressed left ventricular function. The ventricular function improved after surgical subaortic resection without coronary re-vascularisation. This case demonstrates first the rare finding of left main coronary artery atresia and second that coronary re-vascularisation is not necessarily required in all cases of left main coronary artery atresia.

Effects of hypertrophy on left atrial and ventricular compliance and plasma ANF levels in conscious dogs

1995 ◽  
Vol 268 (2) ◽  
pp. H781-H787 ◽  
Author(s):  
N. Hasebe ◽  
L. Hittinger ◽  
S. Kohin ◽  
Y. T. Shen ◽  
R. M. Graham ◽  
...  
Keyword(s):  
Coronary Sinus ◽  
Left Atrial ◽  
Volume Expansion ◽  
Diastolic Pressure ◽  
Systemic Circulation ◽  
Left Ventricular ◽  
Conscious Dogs ◽  
Volume Loading ◽  
Volume Depletion ◽  
Ventricular Compliance

Alterations in left atrial (LA) and left ventricular (LV) compliance and arterial and coronary sinus atrial natriuretic factor (ANF) concentrations at baseline and in response to both volume depletion and expansion were investigated in 15 conscious dogs with aortic banding-induced LV hypertrophy (LVH) (LV/body wt increased by 64%), which also induced LAH (LA/body wt increased by 61%). With volume expansion coronary sinus ANF increased more (P < 0.05) in dogs with LVH (+427 +/- 88 pg/ml) compared with control dogs (+146 +/- 45 pg/ml). Arterial ANF levels also rose more with volume expansion in LVH. In dogs with LVH, the LV end-diastolic pressure-diameter relationship was shifted to the left with a steeper slope with volume expansion, such that at any given diastolic dimension, diastolic pressure was higher. In contrast, the pressure-dimension relationship for the LA appendage was shifted in the opposite direction during both atrial systolic and diastolic phases, with a more shallow slope in hypertrophy compared with control dogs, resulting in an augmented pressure-dimension product during volume loading in LAH. In conclusion, in dogs with LVH and LAH, enhanced ANF was revealed in the coronary sinus and systemic circulation during volume expansion, which could be due, in part, to a more compliant, but hypertrophied, LA, which responded to equivalent volume loading with an augmented pressure-dimension product.

Left ventricular systolic dysfunction precedes diastolic dysfunction during myocardial ischemia in conscious dogs

1994 ◽  
Vol 267 (1) ◽  
pp. H333-H343 ◽  
Author(s):  
T. Ihara ◽  
K. Komamura ◽  
Y. T. Shen ◽  
T. A. Patrick ◽  
I. Mirsky ◽  
...  
Keyword(s):  
Myocardial Ischemia ◽  
Diastolic Dysfunction ◽  
Left Ventricular Systolic Dysfunction ◽  
Systolic Dysfunction ◽  
Left Ventricular ◽  
Conscious Dogs ◽  
Lv Function ◽  
Wall Thickening ◽  
Left Main ◽  
Isovolumic Relaxation

We studied the initial effects of regional and global left ventricular (LV) ischemia induced by left circumflex and left main coronary artery occlusion (CAO), respectively, on indexes of systolic and diastolic LV function in conscious dogs to determine whether diastolic abnormalities precede systolic dysfunction or vice versa during the onset of either regional or global myocardial ischemia. With regional myocardial ischemia, within four beats after left circumflex CAO, there was a significant decrease in end-systolic wall thickness in the ischemic zone followed by significantly enhanced postsystolic wall thickening in the nonischemic zone at beat 6. Both peak negative first derivative of left ventricular pressure (LV dP/dt) and the isovolumic relaxation half-time (T 1/2) were prolonged, but later (i.e., by the 9th beat). During sustained CAO T1/2 was normalized shortly after postsystolic thickening in the nonischemic zone had disappeared despite persistent regional systolic asynchrony and shortened ejection time. Thus postsystolic thickening in the nonischemic zone played a major role in the early, transient changes in isovolumic relaxation after acute induction of regional ischemia. With global myocardial ischemia, induced by left main coronary occlusion, indexes of systolic function (e.g., LV dP/dt, ejection fraction, and velocity of circumferential endocardial fiber shortening) were also depressed significantly before (by 5–15 beats) indexes of LV diastolic function [e.g., time constant of isovolumic relaxation and LV myocardial and chamber stiffness (by 35–45 beats)]. Similar results were observed in the presence of autonomic blockade, when heart rate did not change with CAO. Thus, during the induction of either acute regional or acute global LV ischemia in conscious dogs, LV systolic dysfunction occurs before diastolic dysfunction.

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