Biomedical subjects

K Tsuiki

Publications and source records attributed to K Tsuiki.

At least 55 records · Page 3Linked to original sources

PubMed1989

Improved diagnostic performance on the severity of left ventricular hypertrophy with body surface mapping.

To improve the diagnostic usefulness of electrocardiography (ECG) in determining the severity of left ventricular hypertrophy (LVH) with body surface mapping, 87 unipolar ECGs were recorded from 57 patients with left ventricular (LV) concentric hypertrophy and 30 with LV dilatation. Body surface ECG features due to LVH were evaluated by increase of QRS voltage and delayed local activation. We measured for each lead R voltage, net area of QRS (AQRS), ventricular activation time (VAT), and departure index (DI) of AQRS and VAT (DI = mean/SD). From these measurements, seven parameters were calculated for each patient: Rmax, the maximal R wave voltage; AQRSmax, the maximal AQRS; AQRS-Dmax, the maximal AQRS DI; AQRS-Darea, the area size where DIs of AQRS are more than 2; VATmax, the maximal VAT; VAT-Dmax, the maximal VAT DI; and VAT-Darea, the area size where DIs of VAT are more than 2. Among these parameters, the most effective for diagnosis of LVH were selected by stepwise multiple regression analysis. In the concentric hypertrophy group, the combination of VAT-Darea and Rmax was determined to be the best for estimating wall thickness. The regression equation determined from them correlated well to wall thickness (r = 0.73). In the LV dilatation hypertrophy group, only AQRSmax was selected for estimating LV dilatation. A good correlation between AQRSmax and LV internal dimension was observed (r = 0.73). With the body surface distribution of VAT prolongation, septal hypertrophy was separated from the other LVH. These were superior to the conventional method of 12-lead ECGs. ECG diagnosis of LVH severity improved by incorporating a mapping study. Also, prolongation of VAT and increase in QRS voltage were shown to be important when determining the severity of LVH.

Adolescent↗

PubMed1989

Detection of diseased coronary artery by exercise ST-T maps in patients with effort angina pectoris, single-vessel disease, and normal ST-T wave on electrocardiogram at rest.

To examine the clinical significance of ST-T isopotential maps, 87-lead body surface mapping was performed after treadmill exercise in 21 patients with effort angina pectoris, single-vessel disease, and normal ST-T waves on the resting electrocardiogram. Single-vessel disease was found in the left anterior descending artery (LAD) (nine patients), in the right coronary artery (RCA) (seven patients), and in the left circumflex artery (LCx) (five patients). At 40 msec after the J point, the isopotential maps showed the site of the minimum to be in the left anterior chest in all patients. According to the changes in the position of the minimum from the ST segment to the T wave, postexercise maps were classified into four types. Type A maps (n = 8) were characterized by the persistence of the minimum in the left anterior chest until its negativity decreased and until it became less negative than another minimum that subsequently appeared in a different position. Type B maps (n = 6) were characterized by the gradual movement of the minimum toward the lower thoracic surface. Type C maps (n = 5) were characterized by the gradual movement of the minimum to the left upper direction and then to the back. Type D maps (n = 2) did not show any of the characteristics of A, B, or C. All patients with type A, type B, or type C maps had single-vessel disease of LAD, RCA, or LCx, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Effect of left ventricular volume on right ventricular end-systolic pressure-volume relation. Resetting of regional preload in right ventricular free wall.

Effect of left ventricular (LV) volume on right ventricular (RV) end-systolic pressure-volume relation (ESPVR) was investigated, and the mechanism was examined from a standpoint of the alteration of RV free wall mean fiber length. Twelve cross-circulated isovolumically contracting canine hearts in which both ventricular volumes were controlled independently were used, and RV-ESPVR was determined at three different LV volume levels. At small (10.2 +/- 0.6 ml), middle (15.3 +/- 1.0 ml), and large (20.5 +/- 1.4 ml) LV volume, the slope of the RV-ESPVR was 2.63 +/- 0.13, 2.74 +/- 0.13, and 2.89 +/- 0.12 mm Hg/ml, respectively, and each value was significantly different from the others (p less than 0.01). The volume intercept (V0) of the relation (RV-V0) was significantly decreased with the increment of LV volume (RV-V0 in small, middle, and large LV volume; 3.92 +/- 0.68, 3.39 +/- 0.67, and 2.87 +/- 0.71 ml, respectively; p less than 0.01). In nine hearts, RV free wall lengths in latitudinal and meridional direction were measured at three LV volume levels when RV volume was held constant (16.1 +/- 1.1 ml). RV latitudinal end-diastolic length was significantly augmented with increasing LV volume (latitudinal length in small, middle, and large LV volume; 9.68 +/- 0.55, 9.81 +/- 0.56, and 9.92 +/- 0.55 mm, respectively). RV meridional end-diastolic length also increased significantly with increasing LV volume.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

The correlation of the treadmill exercise test with cardiac hemodynamics in patients with previous myocardial infarction.

The correlation between the treadmill exercise test results and the hemodynamic data of 152 patients with previous myocardial infarction were investigated. The patients were classified into 4 groups as follows: H1 left ventricular end-diastolic pressure (LVEDP) less than or equal to 12 mmHg and cardiac index (CI) greater than or equal to 3.0 L/min/m2; H2 LVEDP greater than 12 mmHg and CI greater than or equal to 3.0 L/min/m2; H3 LVEDP less than or equal to 12 mmHg and CI less than 3.0 L/min/m2; and H4 LVEDP greater than 12 mmHg and CI less than 3.0 L/min/m2. The duration of the exercise was significantly shortened for group H4 than group H1 (p less than 0.01). The maximal ST segment elevation (mSTe) was significantly increased for group H3 and group H4, versus group H1 (p less than 0.05). The number of ST segment elevations and mSTe/maximal heart rate were significantly increased for group H3 (p less than 0.05) and group H4 (p less than 0.01) versus group H1. The incidence of exercise-induced premature ventricular contractions (PVCs) was significantly increased in group H3 and group H4, versus group H1 (p less than 0.05). There were no significant differences in the maximal heart rate, double product, and ST segment depression among the 4 groups. Our data indicate that the groups with impaired left ventricular functions tend to decrease the duration of the exercise and to increase ST segment elevation and PVC frequencies during exercise.

Adult↗

PubMed1989

Spatial distribution of exercise-induced ST-segment depression and U-wave inversion in identifying the ischemic site in patients with coronary artery disease.

Eighty-seven unipolar electrocardiograms were simultaneously recorded before and after symptom-limited treadmill exercise in 75 patients with coronary artery narrowing (greater than equal to 70%) and without previous myocardial infarction. Body surface distributions of ST segment depression were divided into 3 types; upper, lower, and diffuse types. Body surface distributions of U-wave inversion were divided into 2 types; upper, and lower types. These distribution patterns were compared with the location of ischemia determined by T1-201 exercise myocardial perfusion imaging. For ST-segment depression, a considerable number of patients had diffuse-type ST depression, whether the site of ischemia was anterior (22/32, 69%), inferior (18/27, 67%) or both (5/5, 100%). However, upper-type ST depression was associated with anterior ischemia, and lower-type ST depression, with inferior ischemia. The sensitivity and specificity of the spatial distribution of ST depression in identifying the myocardial ischemic site were 27% and 95% for anterior ischemia. The sensitivity and specificity of the spatial distribution of St depression in identifying the myocardial ischemic site were 27% and 95% for anterior ischemia respectively, and 28% and 88% for inferior ischemia, respectively. The incidence of U-wave inversion was moderate (29/75, 39%), but the distribution pattern was specific for the site of ischemia; upper-type U inversion associated with anterior ischemia, and lower type with inferior ischemia. The sensitivity and specificity were 59% and 100% for anterior ischemia respectively, and 22% and 100% for inferior ischemia respectively. By a combination of ST-depression and U-inversion, the sensitivity and specificity were 78% and 95% for anterior ischemia, and 44% and 88% for inferior ischemia. Body surface electrocardiographic mapping provided important information in the non-invasive diagnosis of the site of myocardial ischemia.

Adult↗

PubMed1989

Relationship of thallium-201 defect and left ventricular function after dipyridamole infusion.

Tl-201 imaging and first-pass radionuclide ventriculography (RNV) by 4 min infusion of 0.56 mg/kg dipyridamole were performed on 22 patients with coronary artery disease in order to know the relationship of myocardial perfusion and left ventricular function after dipyridamole-infusion, and thereby to define whether Tl-201 defect with dipyridamole could imply myocardial ischemia. Initial and delayed Tl-201 images were divided into anterior, apical, and infero-posterior segments, and segmental perfusion defects were categorized as reversible, fixed and no defect. RNV on the 30-degree right anterior oblique view was also divided into anterior, apical, and infero-posterior wall to be evaluated for regional wall motion by a 5 point score before and after dipyridamole. Changes in left ventricular ejection fraction (LVEF) with dipyridamole were also calculated. Normal responses of regional wall motion and LVEF to dipyridamole were established from the data of 14 normal subjects. Reversible defects were closely associated (69%) with an abnormal response of regional wall motion (score decrease of 1 or more after dipyridamole). Both fixed defects and no defects showed little association with abnormal response of regional wall motion. Moreover, 77% of the patients having reversible-defect segment showed an abnormal response of LVEF (reduction of 3% or more following dipyridamole). However, patients without reversible defect did not show an abnormal response to dipyridamole. These results suggest that dipyridamole-induced Tl-201 defects represent a myocardial ischemia which causes a reduction of ventricular function.

Adult↗

PubMed1989

[Detection of coronary artery disease by exercise radionuclide ventriculography: using sector analysis].

Exercise first-pass radionuclide ventriculography was performed on 65 patients with coronary artery disease (CAD) and 18 control subjects with normal coronary artery, Left ventricle (LV) was divided into 5 sectors in radial, and volume curves were generated for whole LV and each sector for estimating LVEF and time to end systole (TES). The differences of TES between whole LV and each sector were calculated and these 5 differences were averaged (Variation of TES). We defined this Variation of TES as an index of LV asynchrony, and used for detection of CAD. The overall sensitivity and specificity for identifying CAD were 63% and 83% (LVEF during exercise), 51% and 83% (delta LVEF). Variation of TES during exercise had a sensitivity and a specificity of 88% and 83%, and was more sensitive than both LVEF during exercise and delta LVEF (p less than 0.01). In conclusion, Variation of TES was a good marker of LV asynchrony and useful for the detection of CAD.

Coronary Disease↗

PubMed1988

Diagnosis of right ventricular involvement in chronic inferior myocardial infarction by means of body surface QRS changes.

ST segment elevation in right precordial leads is thought to be good predictor of right ventricular involvement in patients with acute inferior myocardial infarction. This view, however, is rapidly disappearing. Therefore, using QRS changes in body surface potential maps in the chronic phase, we have attempted to differentiate patients with or without right ventricular involvement. Thirty patients with chronic inferior myocardial infarction (2 or more months after onset) were studied, in whom 87 unipolar ECGs and right ventriculograms were recorded. The patients were then divided into three groups depending on the locations of their abnormal QRS potentials (-2SD area) exceeding the normal range (mean -2SD). In group A, the -2SD area was located predominantly on the right inferior chest, in group B on the left inferior chest, and in group N on both the right and left inferior chests equally. The results showed that group A had a lower right ventricular ejection fraction (RVEF) compared with group B (A, 40 +/- 7%; B, 53 +/- 10%; p less than .001), while there was no difference in left ventricular ejection fraction between the two groups (49 +/- 11% and 49 +/- 11%, respectively). Moreover, right ventricular asynergy occurred in 14 of the 18 patients (78%) of group A but in only one of the 10 patients (10%) of group B. Group N was presumed to be intermediate between groups A and B.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1988

Relationship between late potentials and left ventricular function in patients with coronary artery disease.

We examined the relationship between late potentials and left ventricular function from a hemodynamic point of view in 50 patients with prior myocardial infarction. Late potentials were found in 15 (30%) of 50 patients. A left ventricular aneurysm was found in 28 patients. Late potentials were detected in 14 (50%) of 28 patients with the aneurysm but in 1 (5%) of 22 patients without it (p less than 0.01). In the 50 patients, a hemodynamic data from the late potential positive group (n = 15) were compared to those from the late potential negative group (n = 35). The late potential positive group had a significantly lower ejection fraction, cardiac index and stroke volume than the late potential negative group. We further studied the 28 patients with left ventricular aneurysm in a similar way. The cardiac index and stroke volume were also significantly lower in the late potential positive group. The ejection fraction tended to be lower in the late potential positive group. These results suggest that left ventricular function and left ventricular aneurysm are among the factors that influence the development of late potentials.

Adult↗

PubMed1988

Clinical significance of body surface isochrone maps for predicting ventricular arrhythmias in patients with previous myocardial infarction.

To investigate the utility of body surface isochrone maps for estimating ventricular arrhythmias in patients with previous myocardial infarction, we compared findings of body surface isochrone maps with those of signal-averaged electrocardiograms (SAECGs) and an incidence of ventricular tachycardia (VT). Body surface isochrone mapping was performed in 50 patients with previous myocardial infarction. Eighty-seven unipolar electrocardiograms distributed over the patient's anterior chest and back were recorded simultaneously. For each lead, the activation time was measured as the duration from the onset of QRS to the peak of the R wave. SAECGs were recorded in the same patients to detect late potential (LP) which was considered to last more than 30 msec. Activation delay on isochrone maps (D) was found in 31 of 50 patients. The group D+ had a lower ejection fraction and higher incidence of VT (8/31 (25.8%) vs. 1/19 (5.3%)) and LP (13/31 (41.9%) vs. 2/19 (10.5%)) than the group D-. There were four patients with sustained VT who had both D and LP. For predicting VT, D has a sensitivity of 88.9% and a specificity of 43.8%. It was decided that abnormal delay on body surface isochrone maps indicates slow conduction of the surviving myocardium and is related to the occurrence of ventricular arrhythmias. We concluded that body surface isochrone maps can be useful in predicting life-threatening arrhythmias in patients with previous myocardial infarction.

Aged↗

PubMed1988

[Selective augmenting effect of oxy-Hb on the contractions of cerebral arteries elicited by various vasoactive substances].

Serotonin (5-HT), histamine (HA), angiotensin II (ATII), prostaglandin F2 alpha (PGF2 alpha) and thromboxane A2 (TxA2) are known as vasoactive substances, each producing a characteristic contraction of cerebral arteries. These contractions are considered to be mediated by their specific receptors. Recent studies suggest that the activations of these receptors primarily stimulate the phospholipase C and/or phospholipase A2 localized within the same membrane. Stimulation of these enzymes consequently induces production of the second or third messengers such as inositol triphosphate (IP3), diacylglyceride (DAG), arachidonic acid (AA), and ultimately various prostaglandins. The present study is to examine how oxyhemoglobin (Oxy-Hb), another vasoactive substance, can modify these receptor-mediated contractions, and to compare the effects on high K+-, caffeine-and 1-oleoyl-2-acetyl-rac-glycerol (OAG)-induced contractions which are not mediated by the receptors on the cytoplasmic membrane. Helical strips of the bovine middle cerebral arteries (M2) were mainly used in this experiment, and the changes in muscular tensions during isometric contractions were recorded on the polygraph. 5-HT, HA, ATII, PGF2 alpha and cTxA2 (carbocyclic thromboxane A2) were used for each receptor activation. Indomethacin (IDM), a cyclooxygenase inhibitor and 2-nitro-4-carboxyphenyl-n, n-diphenyl-carbamate (NCDC), a phospholipase C inhibitor were used to analyze a possible acting site of Oxy-Hb in modifying these reseptor-mediated enzyme reactions. The results obtained are summarized as follows. (1) All contractions induced by either 5-HT, PGF2 alpha, cTxA2, HA or ATII (concentrations less than 10(-6) M) were markedly augmented as much as 4-8 times the normal, when they were examined in the presence of 10(-5)M Oxy-Hb.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1988

[Multiple arteriovenous malformations of left parietal lobe and left cerebellar hemisphere with symptomatic trigeminal neuralgia: a case report].

The authors described a case of multiple arteriovenous malformations of the left parietal lobe and the left cerebellar hemisphere, and presented a review of literature. A 42-year-old right-handed man was admitted to our Dept. of Neurosurgery on October 20, 1983, with left facial pain and occipitalgia. He had an episode of subarachnoid hemorrhage ten years ago, however, its etiology was not clear at neurological examination. This brief episode of pain began on the left side of his face about 9 years ago and has been gradually increasing. Although he has been treated with trigeminal nerve blocks several times, relapses were almost always evident within 6 months after those nerve blocks. On admission, there were no abnormal findings at neurological and physical examination. A CT scan with contrast medium infusion revealed two small AVMs on the left parietal region and on the left cerebellar hemisphere. A four-vessels cerebral angiogram confirmed the presence of two AVMs and fenestration of the left vertebral artery. The angiogram also revealed that his severe left trigeminal neuralgia had been caused by elongation of the anterior pontine segment of left SCA which was the main feeder of the cerebellar AVM. Two stages of surgical operations were carried out at two months interval. The first operation was total removal of the cerebellar AVM and microvascular decompression for the left trigeminal nerve. The second was total removal of the left parietal AVM. The postoperative course was uneventful, and angiographically the AVMs completely disappeared. The patient was discharged without any neurological deficits on March 11, 1984.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1987

ST segment changes in exercise body surface mapping after myocardial infarction in patients with isolated left anterior descending coronary artery disease.

To investigate the clinical significance of exercise-induced ST segment elevation and ST segment depression after myocardial infarction (MI), we performed 87-lead ECG mapping after previous anterior infarction in 24 patients with isolated left anterior descending coronary artery disease before and 1.5 minutes after treadmill exercise. Thirteen patients showed ST segment elevation only, seven patients showed both ST segment elevation and depression, and four patients showed ST segment depression only. ST segment elevation most frequently occurred in the left anterior chest leads corresponding to the QS area, and ST segment depression developed in the left lower chest and left lower back leads. There was good correlation between the number of lead points showing ST segment elevation (nSTe) after exercise and the number of lead points showing QS waves (nQS) before exercise (r = 0.65). nSTe was also correlated with the asynergy index (r = 0.43). These findings suggest that ST segment elevation is mainly the result of aggravation of wall motion abnormalities of the infarcted myocardium. Body surface distribution of ST segment depression was similar to that in effort angina pectoris without MI. We conclude that exercise-induced ST segment depression in MI mainly reflects the ischemia of the surviving myocardium of small infarcts or the peripheral area of large infarcts.

Adult↗

PubMed1987

Segmental wall motion abnormalities in dilated cardiomyopathy: hemodynamic characteristics and comparison with thallium-201 myocardial scintigraphy.

This study assessed the hemodynamic characteristics of segmental wall motion abnormality of the left ventricle in patients with dilated cardiomyopathy (DCM) and its relation to the thallium-201 (TI-201) myocardial scintigraphy (MPI). Left ventriculograms and MPI in 23 patients were analyzed by the use of quantitative indexes of regional wall motion and TI-201 uptake based on a mean and a standard deviation of 13 normal subjects. Relative normokinesis in our definition was more frequently seen in the inferior wall than in the anterior wall (p less than 0.01). In contrast, severe asynergy was more often seen in the anterior wall than in the inferior wall (p less than 0.01). There were 11 patients who had relative normokinesis and asynergy together. By means of the index of wall motion, the DCM patients were divided into two groups, one with segmental wall motion abnormality (SWMA) and another with diffuse wall motion abnormality (DWMA). The DWMA group had higher left ventricular end-diastolic pressures (p less than 0.05) and the tendency of large left ventricular end-diastolic volumes than the SWMA group. There was a rough correlation (r = 0.58) between the quantitative indexes of TI-201 uptake and wall motion at the same region of the left ventricle. Thus, the nonuniformity of the left ventricular wall motion was recognized in the patients with DCM and more increased preload was shown in the patients with DWMA than in the group with SWMA. Further, the regional asynergy may be related to the localized fibrosis within the left ventricle in DCM, considering the result that the worse TI-201 uptake was roughly accompanied by the more severe asynergy.

Adult↗

PubMed1987

Temporal changes in body surface peak R isochrone maps and left ventricular function in patients with myocardial infarction.

Body surface peak R isochrone mapping and radionuclide ventriculography were performed twice in 22 patients with myocardial infarction. Eighty-seven unipolar electrocardiograms distributed over the anterior chest and the back were recorded simultaneously. For each lead, the time from the onset of QRS to the peak of the R wave was measured. From this data for 87 leads an isochrone map was constructed. The lead points where R waves were not observed were designated the no R-wave area (No-R area), which was postulated to correspond to the unexcited regional myocardium. Other abnormal findings, i.e., delay of peak R time near the No-R area (peri-No-R area delay), crowding of isochrone lines, and an island-like zone of delayed peak R times were postulated to indicate slow conduction in the partially excited regional myocardium. In three patients, abnormal patterns in the peak R isochrone maps during the acute phase (within a month from the onset of myocardial infarction) improved in the chronic phase with a significant increase in left ventricular ejection fraction. In two patients, the No-R area decreased after the left ventricular aneurysmectomy. In other patients, abnormal patterns of the isochrone maps and the ejection fraction remained unchanged during the chronic phase of myocardial infarction. We conclude that the comparison of peak R isochrone map patterns between the acute and chronic phase may be useful in evaluating the balance of reversible and irreversible regional damage in myocardial infarction.

Electrocardiography↗

PubMed1987

Using body surface mapping to detect vulnerability to ventricular arrhythmias in patients with coronary artery disease.

In order to examine the clinical usefulness of the vulnerability map, body surface mapping was performed in ten normal subjects and 32 patients with CAD using dipyridamole infusion to induce ventricular arrhythmias. A vulnerability map and the vulnerability index (VI) proposed by Urie et al. were constructed from QRS and T isointegral maps in the control state and QRST isointegral map after dipyridamole infusion. Premature ventricular complexes (PVCs) did not occur in normal subjects but occurred in 13 patients after dipyridamole infusion. The vulnerability index in normal subjects was significantly lower than that in patients without PVCs (8.3 +/- 1.7 vs 10.4 +/- 1.7, P less than 0.01). Patients with PVCs showed increased density of contour lines in the vulnerability map and significantly higher VI than those without PVCs (12.6 +/- 2.1 vs 10.4 +/- 1.7, P less than 0.01). This result suggests that a higher vulnerability index indicates that the condition of the cardiac muscle is at high risk of ventricular arrhythmias. It is concluded that the vulnerability map is useful for assessing whether or not the cardiac state is at high risk of ventricular arrhythmias in CAD.

Adult↗

PubMed1987

Inhibition of dipyridamole-induced myocardial ischemia by diltiazem in patients with coronary artery disease.

We investigated the effect of diltiazem on dipyridamole-induced myocardial ischemia in eight patients with coronary artery disease. Dipyridamole was infused at a rate of 0.142 mg/kg/min for 4 min, and 87-lead mapping was performed to determine the number of leads with ischemic ST-segment depression greater than or equal to 0.05 mV (nST). The range of nST was 8-24 (mean, 13.8) in the control study. Of eight patients studied, a single dose of 90 mg diltiazem administered 3 h before dipyridamole infusion inhibited dipyridamole-induced ST-segment depression completely in seven (nST = 0) and incompletely in one (nST = from 24 to 5). It was concluded that diltiazem could suppress the myocardial ischemia following dipyridamole infusion.

Aged↗

PubMed1987

The body surface distribution of the QT interval in patients with previous myocardial infarction and normal subjects.

In spite of the clinical importance of the QT interval, its body surface distribution is still unclear. To determine the spatial distribution of the QT interval, we studied 20 normal subjects and 45 patients with previous myocardial infarction (25, anterior; 20, infero-posterior). Unipolar electrocardiograms were recorded from 87 torso sites. The QT interval in each lead was determined semi-automatically. In normal subjects, the longer QT intervals were located on the left anterior chest and the right shoulder portion. And, the relatively shorter QT intervals were shown on the right inferior chest. In the anterior MI group, the remarkably longer QT intervals were located on the left anterior chest. In the infero-posterior MI group, the longer QT intervals were found on the left lateral and back. In both MI groups, the sites of longer QT intervals corresponded to the sites of infarcted area. In the aneurysm (+) subgroup of the anterior MI group, the remarkably longer QT intervals could be found on the left anterior chest, while in the aneurysm (-) subgroup, these characteristic patterns could not be recognized. Our data suggest that QT intervals are not equal on a torso. In patients with myocardial infarction, the sites of prolonged QT intervals corresponded to the sites of infarcted area. The QT interval was thought to have some bearing on the abnormal repolarization of the residual myocardium in the infarcted area.

Aneurysm↗