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Biomedical subjects

J Manthey

Publications and source records attributed to J Manthey.

At least 37 records · Page 2Linked to original sources
PubMed1986

[Surgical indications in mitral valve stenosis, combined mitral valve defect or mitral valve insufficiency. Long-term prognosis of operated or drug-treated patients].

Data obtained from 683 patients with mitral valve disease, NYHA-class III or IV, were retrospectively studied by means of a multivariate Cox regression analysis. Based on symptoms and hemodynamic findings, surgical intervention had been recommended for all patients: closed mitral commissurotomy (n = 361), prosthetic mitral valve replacement (n = 241) and prosthetic mitral valve replacement together with a corrective procedure for the tricuspid valve (n = 81). While the majority of patients underwent surgery during the observation period (n = 528), a substantial number of patients continued on medical treatment (n = 155). The mean observation periods were 52, 49 and 31 months, respectively, in the three collectives. Surgically treated patients in whom closed mitral commissurotomy had been recommended had a better prognosis (p less than 0.0003) than those treated medically (five-year survival rate 89% vs. 63%). Age, clinical severity, previous mitral commissurotomy, pulmonary vascular resistance and right atrial mean pressure had no significant influence on prognosis. In patients in whom prosthetic mitral valve replacement had been recommended, surgical treatment led only to tendencial improvement in prognosis as compared with those treated medically (five-year survival rate 78% vs. 61%). Factors with an unfavorable influence on prognosis were age more than 49 years (p less than 0.05), pure mitral regurgitation (p less than 0.001), NYHA-class IV (p less than 0.02) and right atrial mean pressure in excess of 4 mm Hg (p less than 0.01). In patients in whom prosthetic mitral valve replacement together with a corrective procedure for the tricuspid valve had been considered necessary, surgical treatment had no significant influence on prognosis as compared with those treated medically (five-year survival rate 57% vs. 53%). Patients in whom previous mitral commissurotomy had been performed had an extremely poor prognosis (p less than 0.001). Pulmonary vascular resistance was significantly reduced both after mitral commissurotomy as well as after prosthetic mitral valve replacement; this was associated with a significant decrease in right atrial mean pressure and increase in right ventricular ejection fraction. The indication for closed mitral commissurotomy, thus, appears established in patients with symptoms of class III or IV clinical severity. The indication can be established generously since the surgical mortality is low and long-term prognosis is good.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗
PubMed1985

[Long-term results after local thrombolysis in acute massive pulmonary embolism].

Intrapulmonary arterial infusions of urokinase (mean 1724 IU/kg X h) and heparin (mean 17 IU/kg X h) were given to 7 patients with acute massive pulmonary embolism. Pulmonary angiography and pulmonary artery pressure measurements were performed before, during and 15 months after the drug infusion. During the acute phase, pulmonary artery pressures were recorded daily while urokinase and heparin were administered until the pressures had become normal (after a mean of 6 days). 15 months later right heart catheterization was undertaken before and after ergometric exercise as well as bilateral leg venography. Before treatment pulmonary angiography demonstrated massive vascular obstruction which regressed markedly during and after drug infusion. Treatment also led to normalization of previously elevated pulmonary artery pressures. In addition, pulmonary artery mean pressures and total pulmonary vascular resistance became normal both at rest and on exercise in 6 patients. All patients had signs of acute leg vein thrombosis before treatment, but 15 months later phlebography demonstrated normal findings in 4 and residual findings of previous thrombosis in 3. Local thrombolysis of acute massive pulmonary embolism is thus a highly successful form of treatment.

Adult↗
PubMed1985

Response of alkaline phosphatase to zinc repletion in hypozincemic hemodialysis patients.

The response of serum alkaline phosphatase (AP), a zinc-dependent metalloenzyme, to zinc administration via the dialysate (400 micrograms/l) was examined in 14 hypozincemic (less than 30th percentile of dialysis patients) hemodialysis patients and in 14 placebo-treated matched dialysis control patients. Plasma zinc and serum AP were measured three times: prior to, once weekly during (5 weeks), and 2 weeks after addition of zinc to the dialysate. The serum zinc levels remained stable in placebo-treated controls (initial 87.7 +/- 12.5; final 78.6 +/- 8.3 micrograms/dl) and increased in zinc-treated patients (initial 76.4 +/- 8.3; 5th week 96.9 +/- 13.3; 2 weeks after zinc withdrawal 82.3 +/- 12.2 micrograms/dl). There was a slight increase of AP with time in placebo controls (initial 90.2 +/- 26.5; 5th week 100 +/- 29 U/l) and a more pronounced increase in zinc-treated patients (initial 90.8 +/- 19.9; 5th week 113 +/- 20.9 U/l). The difference between the two groups was marginally significant (p less than 0.05; analysis of variance). It is concluded that zinc repletion via dialysate with documented increase of serum zinc levels in initially hypozincemic dialysis patients causes a reversible increase of serum AP. The result is compatible with some tissue zinc deficiency in hypozincemic dialysis patients.

Adult↗
PubMed1985

Sustained improvement of pulmonary hemodynamics in patients at rest and during exercise after thrombolytic treatment of massive pulmonary embolism.

This study assessed the long-term effects of thrombolytic treatment in patients with acute massive pulmonary embolism (PE). Seven patients with PE that followed deep-vein thrombosis underwent pulmonary angiography and pressure measurements before and 6 +/- 3 days (mean +/- SD) and 15 +/- 4 months after treatment with intrapulmonary infusions of urokinase (average dose 1724 U/kg X hr) and heparin (average dose 17 U/kg X hr). Treatment was guided by daily measurements of pulmonary arterial (PA) pressure and was continued until PA pressure had normalized (average of 6 days). Late after treatment patients returned for pulmonary angiographic examination, right heart catheterization at rest and during bicycle exercise, and phlebography of the deep veins of both legs. Pulmonary angiograms showed massive obstruction before therapy (Walsh index 15 +/- 2 points of a maximum of 18 points), which was improved 6 days (3 +/- 3 points) and 15 months (1 +/- 2 points) after therapy. Mean PA pressure declined from 37 +/- 9 to 13 +/- 3 mm Hg after 6 days and to 15 +/- 3 mm Hg after 15 months. No recurrence of PE was observed. In six of seven patients at rest and during bicycle exercise (up to 100 W) in the supine position mean PA pressure and total pulmonary resistance remained within normal limits. Over the short term all patients showed clinical signs of deep-vein thrombosis; 15 months later four patients had normal deep veins, but three patients had still phlebographic signs of old thrombosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

[Long-term prognosis of drug and surgery treated patients with acquired aortic valve diseases: survival statistics and multivariate Cox regression analysis].

Data of 417 patients with advanced chronic aortic valve disease were retrospectively analyzed using a life table and Cox regression analysis. Aortic valve replacement was recommended to all patients based on clinical and hemodynamic findings. While most patients underwent prosthetic aortic valve replacement (n = 349), a minority of patients was treated medically (n = 68). Prognosis was better (p less than 0.01 in the Cox model) in surgically treated as compared to medically treated patients with aortic stenosis (4-year survival rate 82 versus 44%). In patients with aortic insufficiency no significant difference of long-term prognosis was found between surgically and medically treated patients.

Anti-Bacterial Agents↗
PubMed1984

Effect of successful thrombolytic therapy on right ventricular function in acute inferior wall myocardial infarction.

In 19 patients undergoing intracoronary fibrinolytic therapy for acute myocardial infarction, the site of coronary obstruction was in the proximal right coronary artery. Time between onset of symptoms and hospitalization was less than 4 hours. These patients were studied prospectively by radionuclide techniques immediately after admission, 48 hours and 4 weeks after AMI. Right and left ventricular (RV and LV) ejection fractions (EF) were calculated from gated blood pool scintigrams and the size of the LV perfusion defect was assessed by thallium-201 scintigraphy. Before the intervention, RV performance was significantly lower (RVEF 29 +/- 8%) than normal (53 +/- 7%). The size of the LV perfusion defect was relatively small (less than 25% of LV circumference), and as a consequence, LV pump function was only marginally impaired (LVEF 54 +/- 11%). Recanalization of the infarct artery was achieved in 12 patients (group A); in 7 patients the infarct artery remained occluded (group B). Early after the intervention (48 hours), RV performance in group A recovered significantly (RVEF: 30 +/- 9% vs 39 +/- 7%, p less than 0.01), and further improvement was noted at 4 weeks (RVEF 43 +/- 5%, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Reduction of coronary reserve: a mechanism for angina pectoris in patients with arterial hypertension and normal coronary arteries.

The pathogenesis of angina pectoris in patients with left ventricular hypertrophy secondary to arterial hypertension and with normal coronary arteries remains uncertain. We measured coronary blood flow (argon method) in 12 control subjects and in 16 patients with arterial hypertension at rest and after intravenous administration of dipyridamole (0.5 mg/kg). In the patients with arterial hypertension, coronary blood flow response to dipyridamole was markedly reduced (p less than .001 as compared with control values). During coronary vasodilation there was a linear correlation between coronary resistance and left ventricular end-diastolic pressure (r = .67, p less than .001). Left ventricular catheter biopsy specimens did not reveal alterations in myocardial microvasculature. These findings suggest that reduction of coronary reserve may be an important contributor to the pathogenesis of angina pectoris in these patients.

Adult↗
PubMed1984

Determinants of survival in patients with congestive cardiomyopathy: quantitative morphologic findings and left ventricular hemodynamics.

We analyzed data from 68 consecutive patients with congestive cardiomyopathy to evaluate the prognostic significance of quantitative morphologic findings in left ventricular myocardium as compared with the prognostic significance of left ventricular hemodynamics. Left ventricular endomyocardial biopsy specimens were obtained from all patients during diagnostic heart catheterization. Myocardial fiber diameter, volume fraction of interstitial fibrosis, and intracellular volume fraction of myofibrils were determined by light-microscopic morphometry. All patients had normal coronary arteriograms, but reduced left ventricular ejection fractions. There were 23 deaths during a mean follow-up period of 1124 days. Multivariate regression analysis (Cox model) revealed that left ventricular ejection fraction (p less than .00001) and left ventricular systolic pressure (p less than .01), but not morphometric findings in biopsy specimens, were independent predictors of cardiac death. Thus, morphologic findings in the left ventricular myocardium do not contribute significantly to the prognostic evaluation in patients with congestive cardiomyopathy studied by hemodynamic and angiographic methods.

Adult↗
PubMed1984

[Left ventricular function and activity of vasoconstrictor systems in patients with chronic heart insufficiency].

An increased activity of vasoconstrictor mechanisms may play an important role in circulatory adjustments to heart failure. Thus, hemodynamic data and the plasma hormones epinephrine (E), norepinephrine (NE) and arginin vasopressin (AVP) as well as the plasma renin activity (PRA) were assessed in 50 patients undergoing coronary angiography and right heart catheterization. Patients were classified into three groups according to severity of left ventricular (LV) dysfunction as assessed by ejection fraction (LVEF): those with normal left ventricular function (group 1 (n = 12): LVEF greater than or equal to 55%, mean 70 +/- 3%) and those with moderate (group 2 (n = 16): LVEF 54-35%, mean 43 +/- 2%) or severe LV dysfunction (group 3 (n = 22): LVEF less than 35%, mean 22 +/- 1%). At rest plasma NE concentrations in patients with heart failure (group 2: 187 +/- 17 pg/ml; group 3: 299 +/- 27 pg/ml) did not differ significantly from control values (199 +/- 26 pg/ml). During exercise, NE concentrations increased in all patients (p less than 0.001). This increase in plasma NE was more pronounced in group 3 (753 +/- 71 pg/ml) than in group 1 (262 +/- 37) and group 2 (388 +/- 64). A significant inverse correlation was found between plasma NE and stroke index at rest (r = -0.592, p less than 0.001) as well as during exercise (r = -0.659, p less than 0.001). PRA was elevated at rest and during exercise in patients of group 3 but not of group 2 as compared with control patients (p less than 0.05). Plasma E and AVP were similar in all groups. Patients of group 3 were subdivided according to exercise capacity into patients who tolerated a maximum work load of 50 watts or more (group 3A) and those who did not tolerate a work load exceeding 25 watts (group 3B). At rest and during exercise, patients of group 3A had a higher stroke index than patients of group 3B. In contrast, there was no significant difference in LVEF between group 3A and 3B (22 +/- 2 vs 20 +/- 1%). During exercise patients with low exercise capacity (group 3B) had higher NE levels than patients with less impaired exercise capacity (group 3A) (948 +/- 86 vs 590 +/- 65 pg/ml, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic Disease↗
PubMed1984

[Thrombolysis in acute transmural heart infarction: length of ischemia as a determinant of late results after 15 months].

In 28 patients the effect of coronary artery reperfusion in acute transmural myocardial infarction was evaluated by the clinical and hemodynamic results obtained after 15 months. Patients with successful reperfusion within 4 hours after onset of symptoms were assembled in group A1 (n = 11), patients with successful reperfusion after more than 4 hours in group A2 (n = 7). Group B consists of 10 patients with unsuccessful reperfusion. Left ventricular ejection fraction (radionuclide ventriculography) and the perfusion defect (thallium-201 scintigraphy) were measured acutely and after 15 months (at rest and during exercise). The coronary anatomy and the regional ejection fraction of infarct area were determined acutely and after 4 weeks by cineangiography. Serum creatine kinase activity was measured serially during the acute phase of the infarction. Before the acute intervention, the patients of the 3 groups were comparable with regard to killip class, location of infarction, number of previous infarctions, coronary anatomy, left ventricular ejection fraction, thallium-201 perfusion defect and base-line serum creatine kinase activity. During acute infarction peak creatine kinase activity tended to be lower in group A1 (1296 U/l) than in group A2 (2100 U/l, NS) and in group B (2240 U/l, NS). After 4 weeks regional ejection fraction of infarct area was higher in group A1 (36%) than in groups A2 (24%, NS) and B (20%, p less than 0.05). After 15 months the thallium-201 perfusion defect was smaller in group A1 (7%) than in groups A2 (28%, p less than 0.05) and B (34%, p less than 0.01). At the same time left ventricular ejection fraction was higher in group A1 (52%) than in groups A2 (34%, p less than 0.05) and B (35%, p less than 0.05). Fifteen months after acute infarction patients in group A1 tended to reach a higher workload during exercise (118 watts) compared with patients of groups A2 (82 watts, NS) and B (86 watts, NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1984

[Is the quotient: systolic peak pressure/end-systolic volume a useful parameter in the assessment of left ventricular function?].

The quotient: peak systolic pressure/end-systolic volume (SP/ESVI) has been proposed as a parameter of LV function and as a substitute for the slope k of the end-systolic pressure-volume relation (P-Ves), because SP/ESVI is much easier to obtain. Therefore, the relation between SP/ESVI and k and the relation between SP/ESVI and ejection fraction (EF) were investigated. In 18 patients P-Ves was obtained after vegetative blockade (1.5 mg atropine and 0.15 mg/kg propranolol) from three LV angiograms at three different afterloads (control, isosorbide dinitrate, methoxamine). - SP/ESVI and slope k showed a moderate correlation: SP/ESVI = 0.50k + 2.35; r = 0.76. SP/ESVI and EF were correlated best in an exponential way: SP/ESVI = 0.267 X e0. 045EF ; r = 0.82.- An essential disadvantage of the quotient SP/ESVI resides in the fact, that the P-Ves line has varying intercepts on the abscissa. Secondly, any quotient may belong to several P-Ves lines. The quotient SP/ESVI may be used only with caution and under specific conditions as a substitute of the slope k of the P-Ves.

Blood Pressure↗
PubMed1983

Intracoronary thrombolysis in acute myocardial infarction: an attempt to quantitate its effect by comparison of enzymatic estimate of myocardial necrosis with left ventricular ejection fraction.

The quantity of myocardium was estimated that can be salvaged by reperfusion of acute transmural myocardial infarction (MI). Serial analysis of serum creatine kinase (CK) activity was carried out in 41 consecutive patients with acute MI who underwent intracoronary thrombolysis. Enzymatic estimate of MI size was calculated using an average (method A) and an individually determined elimination constant (method B). Left ventricular ejection fraction 4 weeks after successful thrombolysis (cineangiogram) correlated inversely with MI size (method A: r = -0.85, method B: r = -0.76; both p less than 0.001). Patients with recanalization within 4 hours after the onset of symptoms were assembled in group A1 (n = 13, early reperfusion), and patients with successful recanalization after 4 hours in group A2 (n = 16, late reperfusion). Group B consisted of 12 patients without reperfusion. MI size in group A1 was 21 CK-g-Eq (method A) and 23 CK-g-Eq (method B), in group A2 50 CK-g-Eq (method A) and 54 CK-g-Eq (method B), and in group B 73 CK-g-Eq (method A) and 63 CK-g-Eq (method B). Mean values in group A1 were lower than in group A2 and group B (p less than 0.05). It is concluded that MI size was significantly reduced to about one third after early reperfusion as compared with no reperfusion. In contrast, MI size was not significantly reduced after late reperfusion.

Adult↗
PubMed1983

Coronary dilatory capacity in idiopathic dilated cardiomyopathy: analysis of 16 patients.

Hemodynamic function and overall coronary blood flow (argon technique) were measured in 16 patients with idiopathic dilated cardiomyopathy (IDC) and in 12 patients without detectable heart disease (control subjects) referred for precordial pain. In patients with IDC, coronary blood flow was normal at rest (78 +/- 17 ml/100 g-min versus 78 +/- 9 in control subjects). During maximal inducible coronary vasodilation (dipyridamole, 0.5 mg/kg), coronary blood flow was significantly reduced (142 +/- 38 ml/100 g.min versus 301 +/- 64 in control subjects; p less than 0.001). Consequently, obtainable minimal coronary resistance was increased in IDC (0.54 +/- 0.20 mm Hg/ml/100 g.min versus 0.23 +/- 0.04 in control subjects; p less than 0.001). In patients with IDC, left ventricular (LV) end-diastolic pressure was significantly increased (19 +/- 11 mm Hg versus 6 +/- 3 in control subjects; p less than 0.005), and the LV ejection fraction was diminished (36 +/- 11% versus 72 +/- 3% in control subjects; p less than 0.001). In patients with IDC, LV end-diastolic pressure correlated significantly with the obtained minimal coronary resistance after application of dipyridamole (r = 0.85; p less than 0.001). LV catheter biopsy specimens revealed no alterations in myocardial microvasculature. Thus, coronary dilatory capacity is impaired in patients with IDC, due partially to an increase in extravascular component of coronary resistance.

Adult↗
PubMed1983

Quantitative morphologic findings of the myocardium in idiopathic dilated cardiomyopathy.

This study assesses the relation between quantitative morphologic findings and left ventricular contractile function in patients with idiopathic dilated cardiomyopathy. Left ventricular endomyocardial catheter biopsy specimens were obtained from 73 patients during diagnostic heart catheterization. All patients had normal coronary arteriograms but abnormal electrocardiograms. Twenty-six patients had normal left ventricular function (ejection fraction greater than or equal to 55%), whereas 47 patients had contractile dysfunction (ejection fraction less than or equal to 54%). Myocardial fiber diameter, volume fraction of interstitial fibrosis, and intracellular volume fraction of myofibrils were determined by light microscopic morphometry. Results of light microscopic morphometry were confirmed by electron microscopic morphometry in 12 patients. The coefficient of variation (analysis of several biopsies from the same patient) was 6% for determination of fiber diameter, 43% for interstitial fibrosis, and 3% for volume fraction of myofibrils. Fiber diameter (r = -0.32, p less than 0.01) and fibrosis (r = -0.47, p less than 0.001) showed a negative correlation, the volume fraction of myofibrils (r = 0.55, p less than 0.001) and calculated myofibrillar mass per 100 g of myocardium (r = 0.64, p less than 0.001) a positive correlation with the ejection fraction. Thus, (1) sampling error is low for determination of fiber diameter and myofibrils but high for evaluation of fibrosis, and (2) a reduction in the volume fraction of myofibrils and an increase in fibrosis are morphologic correlates of left ventricular dysfunction in patients with idiopathic dilated cardiomyopathy.

Adult↗
PubMed1982

[Magnesium in serum of patients with coronary heart disease (author's transl)].

In 76 patients with angiographically proven coronary heart disease and in 34 without angiographically demonstrable changes in the coronary vessels, magnesium concentration in serum was measured. The results were compared with the coronary angiographic findings, the left ventricular pump function and the known risk factors. The patients with coronary disease had on average lower magnesium values in serum than the control group (0.835 +/- 0.075 compared with 0.89 +/- 0.08 mmol/l, P less than 0.002). Separation of the coronary patients according to ventricular function showed that only patients with reduced left ventricular function (ejection fraction less than or equal to 55%) had low serum magnesium concentrations when compared with the control group (0.79 +/- 0.075 compared with 0.89 +/- 0.08 mmol/l, P less than 0.001). Patients with coronary disease and normal left ventricular function (ejection fraction greater than 55%) did not differ significantly in their magnesium concentration from the normal controls. The results show that in patients with coronary heart disease lowered serum magnesium concentrations are generally only found when left ventricular function is reduced. The high incidence of sudden cardiac death could be connected with the increased occurrence of low magnesium values in serum of patients with coronary heart disease and diminished ventricular function.

Adult↗
PubMed1982

Intracoronary thrombolysis in acute myocardial infarction: duration of ischemia as a major determinant of late results after recanalization.

To define the effect of duration of myocardial ischemia on the late results after successful thrombolysis in patients with acute transmural myocardial infarction, data on 39 patients treated with intracoronary infusion of streptokinase were analyzed. Patients with successful recanalization of infarct vessel and a time lag between onset of symptoms and reperfusion less than 4 hours were assembled in group A1 (n = 15), and patients with successful recanalization but a time lag of more than 4 hours (n = 17) in group A2. Group B consisted of 7 patients with unsuccessful thrombolysis. Coronary anatomy, left ventricular volume, ejection fraction, and regional ejection fraction of infarct area were determined before and 4 weeks after thrombolysis with cineangiography. Serum creatine kinase activity was serially measured. Before intervention, the groups were comparable with regard to age, Killip class, localization of infarction, incidence of previous infarction, Gensini score of coronary anatomy, left ventricular volume, ejection fraction, regional ejection fraction of infarct area, and serum creatine kinase activity. Four weeks after the intervention, patients in group A1 had a higher ejection fraction (59%) and regional ejection fraction of infarct area (39%) than patients in group A2 (ejection fraction: 49%, p less than 0.05; regional ejection fraction: 26%, p less than 0.05) and group B (ejection fraction: 44%, p less than 0.05; regional ejection fraction: 25%, p = 0.05). Peak serum creatine kinase activity measured during the acute illness was lower in group A1 (764 U/liter) than in group A2 (1,580 U/liter, p less than 0.05) and group B (2,106 U/liter, p less than 0.05). Thus, contraction of infarct area was improved and enzymatic estimate of infarct size was reduced after early as compared with late reperfusion in patients with acute myocardial infarction.

Aged↗
PubMed1982

Thrombolysis in acute myocardial infarction using intracoronary streptokinase: assessment by thallium-201 scintigraphy.

Twenty-one patients with acute myocardial infarction, admitted to the hospital within 4 hours after the onset of symptoms, were studied by seven-pinhole thallium-201 scintigraphy before and 1 hour and 24 hours after intracoronary fibrinolysis using streptokinase. The size of the thallium-201 perfusion defect was assessed from myocardial cross sections reconstructed from the original seven-pinhole data and expressed as a fraction of left ventricular circumference. Recanalization was achieved in 16 patients within 3.9 +/- 1.6 hours after onset of symptoms (group A). In these patients, the size of the perfusion defect had decreased from 36 +/- 17% to 19% +/- 15% (p less than 0.001) at 24 hours. No significant change was detected by redistribution at 1 hour after the intervention. In five patients, intracoronary fibrinolysis was unsuccessful, and the vessel remained occluded (group B). The thallium-201 perfusion defect affected 40 +/- 15% of the left ventricular circumference before the intervention; it remained virtually unchanged at 1 hour (37 +/- 16%) and at 24 hours (41 +/- 15%) after fibrinolysis. The perfusion defect was most reduced in patients with extensive collaterals supplying the ischemic area or with subtotal occlusion of the affected coronary artery. We conclude that successful intracoronary fibrinolysis may reduce the size of the thallium-201 perfusion defect in many patients with acute myocardial infarction. One important factor in the final result may be the presence of residual coronary flow supplied by extensive collaterals or by subtotal occlusion of the affected coronary artery when reperfusion is achieved around 4 hours after the onset of symptoms.

Adult↗