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Query: UMLS:C0022116 (
ischemia
)
91,303
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The coronary hemodynamic effects of controlled
aortic insufficiency
(AI) were studied in 10 dogs. Coronary blood flow (CBF), before and during reactive hyperemia (RH) with graded coronary diameter narrowings (CN), aortic (Ao) and left ventricular (LV) pressures (P), and aortic blood flow (AoF) were recorded. Opening an adjustable basket catheter, positioned across the aortic valve, created reversible AI quantitated from phasic AoF. AI was regulated so that mean CBF was similar with or without AI. During AI, heart rate and systolic AoP were unchanged, but diastolic AoP declined 14 mm Hg (mean) and end-diastolic LVP increased 8 mm Hg, both p less than 0.05. With CN greater than or equal to 85%, mean CBF decreased with or without AI. Coronary resistance was similar with or without AI. During AI with no CN, peak RH CBF declined significantly and was similar to peak RH with 70% CN without AI. Furthermore, AI with 60% CN caused additional reduction in peak RH and was similar to peak RH with 80% CN without AI. These data suggest that CBF reserve, exposed during RH, is decreased during AI. With AI, a given CN has coronary hemodynamic properties similar to higher degrees of CN without AI. These results may relate to clinical findings of
ischemia
in patients with AI and no or moderate CN.
...
PMID:Influence of aortic insufficiency on the hemodynamic significance of a coronary artery narrowing. 15 92
A total of 25 cases (12 men, 13 women) of complete left bundle branch block (LBBB) were found among 1,400 consecutive autopsy in the aged. Their ages ranged from 70 to 86 years (average 78.9). ECG was analyzed as for the occurrence of LBBB and myocardial infarction (MI). Pathological examinations included observations of the conduction system by serial sections. They were divided into group A with MI and group B without MI. Duration of LBBB was 1 to 3 days in 4 cases, more than 1 month in 7, and more than 1 year in 14. From the temporal sequence of LBBB and MI in group A, cases were classified into (1) MI preceding LBBB in 5, (2) both coexistent in 5, and (3) LBBB preceding MI in 1. There were 8 cases of normal electrical axis, 17 left axis deviation, 7 first degree A-V block, and 2 atrial fibrillation. Various heart diseases were underlying in 21 cases, including hypertension, MI, mitral and
aortic regurgitation
, and primary myocardial disease, and there were 4 cases with no cardiac diseases. Cause of death was cardiac in 12; MI, congestive heart failure, and sudden death. Heart weight was 410 Gm on the average (240 to 550 Gm). MI was found in 11, with stenotic index of 12/15, while it was 9/15 in group B. Lesions of the conduction system were slight to moderate (1.5 to 2.4) except left bundle branch, which showed marked changes in posterior (4.9) and anterior (4.8) fascicles. Site of interruption of the left bundle branch was the junction between the branching portion of the A-V bundle and the left bundle branch (Junctional type) in 17, and peripheral portion of the left bundle branch about 10 mm or more below the junction in 8 (Peripheral type). In conclusion, 2/3 of cases of LBBB belonged to the junctional type and most of them were not related to MI, but to the lesions caused by mechanical injuries at the septal summit. One third of the cases were as peripheral type, which was mainly related to the various types of lesions including septal
ischemia
(necrosis and fibrosis).
...
PMID:A clinicopathological study on 25 cases of complete left bundle branch block. 44 51
The records of 12 patients with aortic stenosis previously studied by Fallen et al. in 1967 before and after infusion of isoproterenol were reviewed to assess the value of hemodynamic indexes in predicting myocardial ischemia--defined as less than 5 percent transmyocardial lactate extraction or lactate production. Potential subendocardial blood supply was estimated from a diastolic pressure-time index (DPTI), calculated from the tension-time index (TTI). The ratio DPTI/TTI was used to estimate the supply/demand relation. Of eight patients with aortic stenosis but without associated coronary artery disease, four (Group A) metabolized lactate normally after administration of isoproterenol, and four (Group B) had biochemical evidence of
ischemia
. Three of four patients (Group C) with aortic stenosis and associated coronary artery disease had abnormal glycolysis after administration of isoproterenol. Calculated aortic valve areas were comparable in all groups. In patients with aortic stenosis alone, abnormal lactate metabolism occurred whenever DPTI/TTI was less than 0.30 (P smaller than 0.01) (Group B). Two of three patients with aortic stenosis and associated coronary artery disease (Group C) showed abnormal lactate metabolism when DPTI/TTI was greater than 0.6; this ratio was below 0.3 in the third patient. These results suggest that the supply/demand relation calculated from these readily obtained indexes may be useful (1) in predicting in which patients with aortic stenosis
ischemia
will develop, (2) in distinguishing the role played by associated coronary artery disease, and (3) as an adjunct to calculation of valve area since the quantitation of associated
aortic regurgitation
is not necessary.
...
PMID:Ischemia in aortic stenosis: hemodynamic prediction. 113 Feb 86
The role of surgical therapy for Takayasu arteritis remains controversial. From 1973-1991, 23 patients with Takayasu arteritis have been treated at the University of Southern California. Twelve patients have required 17 arterial reconstructions for symptomatic complications of arterial disease refractory to medical therapy. Indications for operation have included renovascular hypertension (7), extremity
ischemia
(5), cerebrovascular insufficiency (2), dilated ascended aorta with
aortic insufficiency
(1), thoracic aortic aneurysm (1), and abdominal aortic aneurysm (1). Long-term clinical follow-up has demonstrated uniform symptomatic improvement. Fifteen of seventeen arterial reconstructions are still patent. Surgical treatment of symptomatic Takayasu arteritis is highly effective. Excellent long-term graft patency can be expected following arterial reconstruction.
...
PMID:Surgical treatment of Takayasu arteritis. 136 Sep 62
In the past eight years until July 1992, 92 patients were admitted in the acute state of aortic dissection within two weeks from the onset of symptoms. 41 were diagnosed as Stanford type A and 51 were type B by transthoracic and transesophageal echography, computer tomography, and surgery. Sensitivity of transesophageal echography to detect the intimal flap and the false lumen was 97.6% in patients with Stanford type A and 100% in patients with Stanford type B. The surgical decision making has been mostly depending on the transesophageal echographic diagnosis. When the intimal flap was detected in the ascending aorta (Stanford type A) surgery was performed in emergency regardless of any evidence of rupture, cardiac tamponade, and severe
aortic regurgitation
. When the aortic dissection was detected only in the descending aorta (Stanford type B) the main course of therapeutic strategy in our institute was medical treatment. Surgery was performed on 37 patients of type A and nine patients of type B with mortality of 18.9% and 55.5% respectively. Four patients of type A and 42 patients of type B were treated medically with a mortality of 75.0% and 2.2% respectively. The relatively large leakages from the anastomosis of the aortic clamp site were repaired secondarily in two patients, and fenestration of the superior mesenteric artery was performed on one patient due to
ischemia
of the small intestine depending on the intraoperative direct scanning of color flow mapping. Coronary artery involvement of dissection was strongly suspected in two patients by intraoperative transesophageal echography and aortocoronary bypass grafting was performed on these patients. Perfusion problems was encountered in five of 37 patients with type A aortic dissection (13.5%) during cardiopulmonary bypass. Intraoperative transesophageal echography could clearly detect the hemodynamic changes in the descending aorta resulting from inadequate perfusion which was useful for the management of perfusion control during cardiopulmonary bypass. Secondary repair of the aortic arch was required due to
ischemia
of the aortic arch vessels in two patients after the primary surgery. The extension of the dissection into the aortic arch vessels can be promptly diagnosed with the combination of transesophageal echography and transcutaneous echography. In conclusion, transesophageal Doppler echography is the most rapid diagnostic tool for decision making in acute aortic dissection, and intraoperative transesophageal echo can provide useful information to resolve the perfusion difficulties during cardiopulmonary bypass.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Intraoperative echocardiography for diagnosis and treatment of aortic dissection. Utility of color flow mapping for surgical decision making in acute stage. 148 26
Eighteen of 25 survivors of aortic valvotomy in infancy were reinvestigated by cross-sectional echocardiography a mean of 7.5 (2.3-13.4) years after surgery. They had been operated at a median age of 38 (5-330) days. At the follow-up examination the gradient across the aortic valve was 41 +/- 19 (15-85) mmHg and the ejection fraction was 0.73 +/- 0.10 (0.48-0.84). Left ventricular (LV) end-diastolic volume was 66 +/- 17 (33-191) ml/m2. LV mass was 96 +/- 36 (44-204) g/m2 and the LV mass volume index (LVMVI) (mass divided by end-diastolic volume) was 1.43 +/- 0.4 (0.9-2.28). Eleven of 18 patients had an abnormally high mass volume index compared with 95 age-matched controls with structurally normal hearts. The correlation between the residual pressure gradient across the aortic valve and mass volume index yielded an r value of 0.75 (p less than 0.0004). One patient had been reoperated and underwent resection of a subaortic stenosis 4 years after the initial operation. Four patients with a resting gradient of more than 50 mmHg and one with grade 4
aortic regurgitation
are scheduled for further surgical treatment. We conclude that, although LV function was normal in most patients who underwent aortic valvotomy in infancy, LV mass remains elevated in a significant number of patients, who may remain at risk of developing subendocardial
ischemia
.
...
PMID:Left ventricular function and myocardial mass after aortic valvotomy in infancy. 173 70
Although the difficulty of preserving hypertrophied myocardium from induced arrest during aortic clamping has long been recognized, the difference of response to
ischemia
between the two types of hypertrophy induced by pressure-loading (P) and by volume overloading (V) has not been fully elucidated. In the present study, to assess the two types of hypertrophied myocardium we investigated the 44 patients undergoing valve replacement; the 23 patients of aortic stenosis (AS) without
aortic regurgitation
(AR), and the 21 patients of AR without AS. The patients of AS (group-P) were divided into two groups regarding the thickness of posterior wall of left ventricle; over 15 mm in P-1 and under 15 mm in P-2. The patients of AR (group-V) were also divided into two groups, which is, preoperative LVEDVI over 250 ml/m2 in V-I and under 250 ml/m2 in V-2. In all four groups myocardial temperature was kept about 5 degrees C with GIK and continuous cold blood coronary perfusion during aortic clamping time. There was no operative death. Postoperative serum enzymes (GOT and CPK) in P-1 were higher than in P-2. Per cent increase of LVEF in P-1 were greater than P-2 and V-1 greater than V-2, respectively. Postoperative catecholamines needed for P-1 was greater than P-2.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:[Protection of the two types of severely hypertrophied myocardium induced by pressure-loading and by volume overloading]. 183 32
To determine which therapeutic procedure is most appropriate for which type of aortic dissection, we investigated 146 cases of acute aortic dissection. In the group with dissection of the ascending aorta, 58.6% of patients given medical therapy and 48.8% of patients given surgical therapy died. In the group with dissection of the descending aorta, 14.0% given medical therapy and 50.0% given surgical therapy died. High mortality in the medical group with type A dissection was caused by delayed operation. Better survival was achieved in treated than surgically treated patients with acute distal dissection. In patients with cardiac tamponade,
aortic regurgitation
, hemothorax/hemo-mediastinum, visceral
ischemia
and peripheral
ischemia
, mortalities following medical treatment were fairly high. Surgical treatment brought on improvement in mortality in these groups. However, in the cases complicated by renal dysfunction, the mortality in the surgical group was higher than that in the medical group. 42 patients (28.8%) had no evidence of any complication and only 6 (14.3%) died. In 20 cases (47.6%) of uncomplicated dissection, no blood flow was observed in the false lumen. In cases with open false lumen, the following abnormal findings were more conspicuous: thrombocytopenia, decreased level of fibrinogen, increased fibrin degradation product and soluble fibrin monomer complex. However, these changes seem to be minimal in cases with thrombosed false lumen. The measurement of coagulation factors may be one useful method to determine which therapeutic procedure is most suitable.
...
PMID:Medical vs surgical treatment of acute aortic dissection in an intensive care unit. 189 14
Takayasu's arteritis is an inflammatory arteriopathy that often progresses to obliteration of multiple large arteries. Variable results have been reported after medical and surgical management. Twenty female patients with Takayasu's arteritis were treated from 1973 to 1989. Eleven (55%) patients had hypertension. Upper or lower extremity
ischemia
was present in 12 (60%) patients and cerebrovascular insufficiency in seven (35%). Nine patients initially managed with corticosteroids had no improvement in signs or symptoms of arterial insufficiency. Eleven patients had 16 vascular procedures for the following indications: renovascular hypertension (6), extremity
ischemia
(5), cerebrovascular insufficiency (2), dilation ascending aorta with
aortic insufficiency
(1), thoracic aortic aneurysm (1), abdominal aortic aneurysm (1). Procedures included aortorenal bypass (5), carotid-subclavian, axillary, or brachial bypass (4), aorto-carotid bypass (2), aneurysm resection (2), supra-celiac aorto-femoral bypass (1), ascending aorta/aortic valve replacement (1), and nephrectomy (1). Clinical improvement occurred in all patients. There were no operative deaths. All are alive at a mean follow-up of 5.75 years (6 months to 16 years). Revision of the initial reconstruction has been required for recurrent renovascular hypertension in one patient and extremity
ischemia
in another. The other nine patients remain symptomatically improved. Symptomatic Takayasu's arteritis frequently requires arterial reconstruction. Symptomatic improvement and excellent long-term graft patency can be expected after arterial reconstruction.
...
PMID:Surgical procedures in the management of Takayasu's arteritis. 197 28
To elucidate the incidence and natural history of valvular heart disease in Kawasaki syndrome, we analyzed patients who were found to have a new heart murmur after the onset of the disease. Among 1215 patients we found 13 (1.1%) with valvular disease (12 with mitral regurgitation and one with
aortic regurgitation
). We compared these patients with 30 who did not have valvular lesions. The duration of fever was longer and the incidence of coronary artery lesions significantly higher than in those without valvular disease. Heart murmurs disappeared within 2 months after the onset of valvular heart disease in five patients, whereas in another six, all involving valve prolapse, they persisted for 2 years or more. We postulate that two different mechanisms may be responsible for the variation in the duration of valvular heart disease: one, which disappeared spontaneously, was attributed to pancarditis; the other, which persisted, was due to dysfunction in valve and papillary muscles as a result of
ischemia
.
...
PMID:Valvular heart disease in Kawasaki syndrome: incidence and natural history. 238 13
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