Is warfarin associated with higher risk of thrombus in left atrial appendage than direct oral anticoagulants?

Funding Acknowledgements

Type of funding sources: None.

Background

Thrombus in left atrial appendage (LAA) is associated with cardiogenic ischemic stroke, and anticoagulation therapy is utilized to prevent thromboembolism.

Purpose

This study is to investigate the incidence of thrombus in left atrial appendage detected by transoesophageal echocardiography (TOE) under anticoagulation therapy with warfarin or direct oral anticoagulants (DOAC).

Methods

Between 2005 and 2016, the patients who underwent TOE under anticoagulation therapy due to atrial fibrillation more than one month were enrolled in this study. The patients were divided into 2 groups according to whether treated with warfarin or DOAC and baseline characteristics and incidence of LAA thrombus were assessed.

Results

Among the 313 study patients, 243 (78%) were treated with warfarin. The patients treated with warfarin were elder (median 73 y vs. 67 y [interquartile range 66 – 78 y vs. 58 – 72 y], P < 0.01), the body mass index was lower (23.2 vs. 24.0 [21.0 – 25.4 vs. 21.3 – 26.9], P = 0.03). The prevalence of male sex (64% vs. 71%, P = 0.26) were similar between the 2 groups. The previous history of hypertension (69% vs. 59%, P = 0.10), diabetes (24% vs. 19%, P = 0.32), vascular disease (30% vs. 26%, P = 0.52), and ischemic stroke were similar between the 2 groups (30% vs. 23%, P = 0.22). The prevalence of CHA2DS2-VASc score > 1 (84% vs. 59%, P < 0.01) and the d-dimer level (0.7 vs. 0.5 mcg/ml [0.5 – 1.8 vs. 0.5 – 0.5 mcg/ml], P < 0.01) were higher in the warfarin groups than those of the DOAC. The velocity of LAA was slower in the warfarin group than those of DOAC (35 vs. 55 cm/s [21 – 54 vs. 38 – 68 cm/s], P < 0.01). The incidence of detection of LAA thrombus was 19% in the warfarin group and 3% in the DOAC group (P < 0.01). In the warfarin group, the PT-INR were lower in the patients with LAA thrombus (1.38 vs. 1.66 [1.11 – 1.92 vs. 1.34 – 2.03], P = 0.03).

Conclusions

The higher risk of ischemic stroke and out of range PT-INR may be the cause of the higher incidence of LAA thrombus in the patients treated with warfarin than those with DOAC.

Abstract Figure.

Prognosis and cause of death in patients with left atrial appendage thrombus treated with or without anticoagulation therapy

Background

Thrombus in left atrial appendage (LAA) is associated with cardiogenic ischemic stroke; however, little is known about prognosis of patients with LAA thrombus detected by transoesophageal echocardiography (TOE).

Purpose

This study is to investigate the prognosis of patients with LAA thrombus and their cause of death.

Methods

Between 2005 and 2016, the patients who were performed TOE in our hospital were enrolled in this retrospective observational study. Five-year stroke free and survival curves were constructed by Kaplan-Meir method and cause of death were assessed.

Results

Among the 1263 study patients, LAA thrombus was detected in 146 (12%) patients. The patients with LAA thrombus were elder (74 y [66–79 y] vs. 70 y [62–76 y], P<0.001), than those without LAA thrombus, respectively. The prevalence of male sex (67% vs. 69%, P=0.63) were similar between the 2 groups. The prevalence of CHA2DS2-VASc score ≥2, d-dimer (1.7 mcg/ml [0.9–3.5 mcg/ml] vs. 0.8 mcg/ml [0.5–2.2 mcg/ml], P<0.001), and plasma brain natriuretic peptide (315 pg/ml [128–515 pg/ml] vs. 126 pg/ml [47–284 pg/ml], P<0.001) were higher in the patients with LAA thrombus than those without (89% vs. 78%, P=0.003). The LAA velocity was slower in the patients with LAA thrombus than those without (23 cm/s [15–34 cm/s] vs. 51 cm/s [35–72 cm/s], P<0.001). The prevalence of receiving anticoagulation therapy before (34% vs. 24%, P=0.01) and after (98% vs. 66%, P<0.001) TOE 1 month were higher in the patients with LAA thrombus than those without. The 5-year stroke free rate was lower in the patients with LAA thrombus than those without (82% vs. 93%, P<0.001); however, the 5-year survival were similar between the 2 groups (84% vs. 84%, P=0.93) (Figure). The cause of death as ischemic stroke was only 7% (1/14) and 3% (3/94), (P=0.43); the cardiac cause (14% vs. 43%, P=0.07) and the malignancy (35% vs. 29%, P=0.75) were the frequent cause of death in the patient with LAA thrombus and those without, respectively.

Conclusions

The patients who were detected thrombus in the LAA had higher incidence of ischemic stroke; however, the 5-y survival were similar. The ischemic stroke was not major cause of death in the patients with and without LAA thrombus. The higher rate of receiving anticoagulation therapy may be one of the causes of the discrepancy.

Figure 1

Funding Acknowledgement

Type of funding source: None

P684 Paradoxical cerebral infarction due to massive pulmonary embolism in extracorporeal cardiopulmonary resuscitation and surgical embolectomy

Introduction

Paradoxical cerebral infarction is a mechanism of acute ischemic stroke; however, definitive images to diagnose paradoxical embolism are not often obtained. We report a case of paradoxical cerebral embolism complicated with cardiac arrest due to massive pulmonary embolism.

Case report

A 40-year-old man presented due to sudden-onset chest pain, and was admitted to our hospital. He was restless and had cold sweat; we could not measure blood pressure. Electrocardiography showed wide QRS complex with right bundle branch block, and T wave inversion in leads V1 and III. Transthoracic echocardiography showed diffuse severe left ventricular hypokinesis, with slightly better inferior wall motion compared to other segments. Few minutes after arriving, he experienced cardiac arrest; chest compression was initiated. He was transported to the catheter laboratory, and veno-arterial extracorporeal membrane oxygenation was initiated subsequently. To diagnose the cause of arrest, we performed coronary angiography, which revealed no occluded coronary artery. Pulmonary angiograms showed bilateral proximal pulmonary artery occlusion with massive thrombi (panel A). Surgical embolectomy was performed after cardiac team discussion. After ICU admission post-surgery, pericardial effusion was increased, and the blood drained continuously from the chest tube; a large amount of blood transfusion was required. Reopen chest haemostasis was utilised. After the second ICU admission, anisocoria was observed; subsequent computed tomography showed low density and midline shift in almost the entire left cerebral hemisphere (Panel B). Carotid duplex ultrasound revealed a large thrombus saddled at the left carotid artery bifurcation (Panel C and D). We rechecked the transthoracic echocardiogram at arrival to reveal the cause of the cerebral infarction, which showed the thrombus to be at the ascending aorta (Panel E). We thought that the thrombi had moved from the lower limb to the right atrium. The massive pulmonary embolism increased the pulmonary artery and right atrial pressure, resulting in the lower pressure of the left atrium compared to that of the right atrium. The thrombi passed through the patent foramen ovale into the left atrium, moved into the left ventricle, and embolised the left internal carotid artery (Panel F). He expired due to severe neurologic injury from brain herniation.

Conclusion

In this case, although the pulmonary embolism was massive and led to cardiac arrest, the deteriorated haemodynamics improved by extracorporeal cardiopulmonary resuscitation and surgical embolectomy. However, we could not rescue the patient because of the severe neurological injury due to paradoxical embolism. Paradoxical cerebral infarction in pulmonary embolism is rare; however, we should pay careful attention to early detection of paradoxical cerebral infarction in pulmonary embolism and treatment for return of the patient to the former lifestyle.

Abstract P684 figure

P765 Does detection of thrombus in left atrial appendage increase risk of ischemic stroke and mortality?

Background

Left atrial appendage (LAA) thrombus is one of causes of cardiogenic stroke and detection of LAA thrombus by transoesophageal echocardiography (TOE) strongly suggest cardiogenic stroke. It was reported that cardiogenic stroke patients had higher in-hospital mortality about 19%; however, little is known about LAA thrombus and mortality after indexed detection of LAA thrombus. We investigated LAA thrombus detection and their prognosis including ischemic stroke and survival.

Methods

The patients who were performed TOE between 2005 and 2016 in our hospital were enrolled in this study. Patients were divided into 2 groups based on thrombus detection in the LAA, and baseline characteristics and outcomes including prevalence of 5-y stroke-free and survival from the indexed TOE were compared.

Results

Among the 1260 study patients, the follow-up duration was median 971 d (interquartile range 345 d – 2017 d), and 67% of the patients were performing TOE for atrial fibrillation (AF), 20% for cerebral infarction, and 14% for valvular heart disease. Non-valvular AF was seen in 64% of the study patients and rheumatic AF was in 2%. The age (74 y [66 y – 79 y] vs 70 y [62 y – 76 y], p < 0.001), the prevalence of male sex (67% vs 69%, p = 0.63), and hemoglobin level (13.9 g/dl [12.5 – 15.1 g/dl] vs 13.8 g/dl [12.4 – 14.9 g/dl], p = 0.49) were similar between the patients with LAA thrombus and those without. The CHA2DS2-VASc score (p = 0.008), the prevalence of receiving anticoagulation before TOA (34% vs 24%, p = 0.01), those of after TOA (98% vs 66%, p < 0.001), serum creatinine (0.92 mg/dl [0.80 – 1.10 mg/dl] vs 0.85 mg/dl [0.71 – 1.00 mg/dl], p < 0.001), d-dimer level (1.7 mcg/ml [0.9 – 3.5 mcg/ml] vs 0.8 mcg/ml [0.5 – 2.2 mcg/ml], p < 0.001), and plasma brain natriuretic peptide (315 pg/ml [128 – 515 pg/ml] vs 126 pg/ml [47 – 284 pg/ml], p < 0.001) were higher in the patients with LAA thrombus than those without. The 5-y ischemic stroke-free rate was lower in the patients with LAA thrombus than those without (p < 0.001) (Figure, Panel A); however, the 5-y survival was similar between the 2 groups (p = 0.93) (Panel B).

Conclusions

The patients who were detected thrombus in the LAA had higher incidence of ischemic stroke, but the survival rate were similar. The higher rate of receiving anticoagulation therapy in the patients with LAA thrombus may be the cause of this discrepancy. Further studies are necessary to clarify this issue.

Abstract P765 Figure

P4548Early drop in systolic blood pressure and worsening renal function in the elderly acute heart failure: how does heart rate interact?

Background

Renal dysfunction is a frequent finding in patients hospitalized for acute heart failure (AHF). Worsening renal function (WRF) during hospitalization was found to be related with a poor outcome independently of baseline renal function. Early drop in systolic blood pressure (SBP) has shown to predict WRF in AHF. However, there have been few studies that reported the impact of on-admission heart rate (HR) on the relationship between early SBP drop and WRF in the elderly AHF.

Purpose

We assessed the hypothesis that early SBP drop predict WRF in the elderly patients with AHF, and investigated that on-admission HR might have an interaction with that relationship.

Methods

SBP and HR were measured on admission and 6 times during 48 hours in the 245 elderly AHF inpatients (82.9±6.0 years old, male 49.4%). WRF was defined as a serum creatinine increase of ≥0.3 mg/dL by Day 5. Early drop in SBP was calculated as the difference between admission and the lowest value measured during the first 48 hour of hospitalization.

Results

Early SBP drop (51.3 vs 32.5mmHg, p<0.01) and on-admission HR (79.3 vs 89.6bpm, p<0.05) were significantly different between the group with WRF (n=36) and the group without WRF (n=209). In the multiple logistic regression analysis adjusted for the confounders including age, gender, hypertension, left ventricular ejection fraction, total cholesterol, BNP, baseline creatinine, beta-blockade use, intravenous loop diuretic, isosorbide dinitrate and carperitide use, early SBP drop (OR: 1.003, 95% CI: 1.003–1.03, p<0.04) and on-admission HR (OR: 0.98, 95% CI: 0.96–0.99, p<0.01) were significantly associated with WRF. The interaction term of early SBP drop by on-admission HR did not have a significant association with WRF (p=0.3).

Conclusions

In the elderly AHF patients, exaggerated early SBP drop and lower on-admission HR were shown as significant independent predictors of WRF. These two factors were additively associated with WRF. Too much reduction in SBP and that in HR might be harmful to renal circulation in AHF.

MRI findings of mucoepidermoid carcinoma of the parotid gland: correlation with pathological features

OBJECTIVE

The aim of this study was to correlate the MRI appearance and pathological findings in each grade of the mucoepidermoid carcinoma (MEC) of the parotid gland.

METHODS

We reviewed surgically proven MECs of parotid glands in 20 patients. Pathologically, 5 tumours were high-grade, 3 were intermediate and 12 were low-grade. MR images were evaluated with emphasis on signal intensities on T(2) weighted images, margin characteristics and lymph node metastasis, correlating these with pathological features.

RESULTS

Among the high-grade MECs, four out of five tumours showed inhomogeneous low to intermediate signal intensity on T(2) weighted images, reflecting high cellularity. All tumours had an ill-defined margin, reflecting invasive tumour growth. Among the intermediate-grade MECs, all three tumours showed intermediate signal intensity on T(2) weighted images and two tumours had an ill-defined margin. Among the low-grade MECs, 11 of the 12 tumours had a hyperintense area on T(2) weighted images because of the existence of abundant mucin secreting cells. Seven tumours had an ill-defined margin, reflecting peritumoural inflammatory changes rather than invasive tumour growth. Lymph node metastasis was seen in three high-grade MECs.

CONCLUSION

MECs of the parotid gland show variable MRI findings reflecting their histological nature, which seems to have certain tendencies depending on the tumour grade.

Myocardial performance index for assessment of left ventricular outcome in successfully recanalised anterior myocardial infarction

OBJECTIVE

To investigate whether the myocardial performance index (MPI) can predict left ventricular functional outcome in patients with early recanalisation after anterior acute myocardial infarction (MI) and to determine when the index should be measured.

DESIGN

MPI was measured serially by two dimensional Doppler echocardiography after successful percutaneous coronary intervention (PCI). Left ventricular function was evaluated by echocardiography and left ventriculography. To assess coronary microvascular damage, the coronary flow velocity pattern was measured immediately after PCI with a Doppler guidewire.

SETTING

Hiroshima City Asa Hospital.

PATIENTS

32 consecutive patients with their first anterior acute MI who had complete occlusion of left anterior descending coronary artery.

INTERVENTIONS

Successful PCI within six hours of symptom onset.

MAIN OUTCOME MEASURES

Left ventricular anterior wall motion score index (A-WMSI), left ventricular end diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and left ventricular end diastolic volume (LVEDV).

RESULTS

There was a significant negative correlation between MPI on day 2 and the coronary diastolic deceleration time (r = -0.66, p < 0.002), as well as a significant positive correlation with the coronary diastolic deceleration rate (r = 0.74, p < 0.0001). MPI on day 2 was significantly correlated with the short and long term changes of A-WMSI and with the short term changes of LVEDP. Furthermore, MPI on day 2 was significantly correlated with the short and long term changes of LVEF (r = -0.52, p < 0.003, and r = -0.64, p < 0.0008, respectively) and of LVEDV (r = 0.51, p < 0.003, and r = 0.41, p < 0.05, respectively).

CONCLUSIONS

Doppler derived MPI on day 2, representative of the early coronary microvascular state, can predict the left ventricular functional outcome after early successful recanalisation of a patient's first anterior acute MI.

New pain following cordotomy: clinical features, mechanisms, and clinical importance

OBJECT

The clinical features, possible causes, and contributing factors associated with novel spontaneous pain following unilateral cordotomy were investigated to clarify the mechanism and clinical importance of this pain.

METHODS

Forty-five patients who underwent cordotomy for severe unilateral cancer pain were included in this study. New pain occurred in 33 (73.3%) of 45 patients. Pathological conditions of tissue demonstrated on imaging corresponded to new pain in eight patients, referred pain in five, and neither of these in 15 patients. New pain was centered opposite the site of the original pain in a mirror-image location in 28 patients and rostral to the original pain in five patients. It was temporary in seven patients, weaker than the original pain in 25, and as severe as the original pain in one patient. The incidence of moderate or severe pain was significantly higher in patients with confirmed tissue disease (six of eight patients) than in those without (six of 20 patients). An important contributing factor to the occurrence of new pain was the achievement of analgesia by performing the cordotomy.

CONCLUSIONS

The present results indicate that new pain occurs frequently after unilateral cordotomy. Nonetheless, cordotomy may still be indicated for unilateral uncontrollable pain because new pain, when present, was weaker and more easily controlled than the original pain in nearly all cases. The authors speculate that new pain may represent a type of referred pain from the original painful area or may arise from sensitization of contralateral spinal nociceptive circuits due to metastasis or tumor infiltration, and that new pain is potentiated by the interruption of descending inhibitory pathways.

Biological functions of extravasated serum IgG in rat brain

During blood-brain barrier opening serum IgG could be extravasated. The function of intraparenchymal IgG, however, is unknown. Its biological effects in the acute phase were currently investigated. From rat autoserum IgG was purified and injected into the cortex. Similarly, IgG-Fab fragment was prepared and administered likewise. As for the control group, only vehicle was injected. Animals were sacrificed on days 1, 2 and 4 after the infusion and were histologically evaluated. On days 1 and 2, the infusion of IgG caused significant intraparenchymal infiltration of neutrophils which expressed LFA-1-alpha. It also induced CR3 up-regulation in microglia and endothelial ICAM-1 expression. On day 4, these findings had disappeared. HE stained brain sections and the TUNEL method did not reveal significant nerve cell death in IgG injected animals during the experiment as compared to the controls. IgG-Fab did not cause significant changes either. Extravasated IgG has been viewed to have biochemical functions. Its Fc fragment seemed to cause microglial and endothelial activation, followed by leukocytic infiltration. This sequence itself was not neurotoxic. Therefore, it is suggested that extravasated IgG is one of the inducers that modulate cellular responses in the acute phase of brain damage.

Ischemic preconditioning suppresses the noradrenaline turnover in the rat heart

OBJECTIVE

The mechanism by which ischemic preconditioning protects the heart is presumed to be related to the reduction of energy consumption during a subsequent myocardial infarction. Since the sympathetic nervous system enhances cardiac function and energy consumption, we investigated the relation between ischemic preconditioning and the turnover rate of noradrenaline (NA) in the rat heart.

METHODS

The effect of 3 cycles of 5-min occlusions of the rat left coronary artery on changes in arterial blood pressure and heart rate provoked by a subsequent 30 min of ischemia were examined until 60 min after reperfusion. The effect of 3 cycles of occlusions on the infarct size was also evaluated 60 min after reperfusion by comparing the infarcted area with the area at risk in these animals (6 per preconditioned and sham-operated group). The tissue concentration of NA during sustained ischemia was determined in the left ventricle, the intraventricular septum, and the right ventricle in the preconditioned and sham-operated groups. Changes in the turnover rate of NA after 3 cycles of occlusions were also evaluated by assessing the alpha-methyl-p-tyrosine-induced depletion of NA (n = 7 per group).

RESULTS

A series of transient occlusions reduced the infarct size 60 min after a sustained ischemia for 30 min. Arterial pressure and heart rate were not affected. The concentration of NA was decreased in the left ventricle 60 min after the onset of sustained ischemia in both the preconditioned and sham-operated groups. The treatment with alpha-methyl-p-tyrosine decreased the NA concentration in all regions of the heart in the sham-operated group after 60 min. However, the treatment with alpha-methyl-p-tyrosine did not deplete the NA concentration in both the occluded and nonoccluded regions in the preconditioned group.

CONCLUSIONS

Transient ischemia ameliorated the heart injury induced by a subsequent sustained ischemia, as assessed histologically. The activity of the sympathetic nervous system in all regions of the heart was reduced by transient ischemia in the left coronary vascular bed. These findings suggest that the inhibition of the sympathetic nervous system by the treatment of ischemic preconditioning takes part in the cardiac protection.

Hypothermia increases the threshold for ischemic preconditioning

OBJECTIVES

Both hypothermia and ischemic preconditioning are known to provide tolerance to myocardial ischemia and reperfusion. The aim of this study was to determine whether hypothermia during the ischemic preconditioning period attenuates the protective effect of ischemic preconditioning.

METHODS

Experiments were performed in buffer-perfused isolated rabbit hearts. All hearts underwent 45 minutes of regional ischemia, followed by 2 hours of reperfusion. Ischemic preconditioning was elicited by either one or four periods of 5 minutes of regional ischemia. Hypothermia (25 degrees C) was induced beginning either 20 or 50 minutes before the 45-minute period of regional ischemia; normothermia (38 degrees C) was restored 10 minutes before the 45-minute period of regional ischemia. Except for the hypothermic periods noted, hearts were maintained at 38 degrees C.

RESULTS

Normothermic ischemic preconditioning with either one or four cycles of 5 minutes of coronary occlusion resulted in a profound reduction of infarct size (58% reduction with one cycle, p < 0.05; 95% reduction with four cycles, p < 0.01). Hypothermic ischemic preconditioning with one cycle of 5-minute coronary occlusion resulted in no reduction of infarct size but hypothermic ischemic preconditioning with four cycles of 5-minute coronary occlusions resulted in a 94% reduction of infarct size (p < 0.01). Myocardial glycogen and lactate levels were maintained near control levels during hypothermic ischemia.

CONCLUSIONS

From these data we conclude that hypothermia during the preconditioning period increases the threshold for eliciting the infarct limitation of ischemic preconditioning.

[Percutaneous drainage of a bulla with tuberculous infection in a patient]

A 63-year-old man complaining of low grade fever and dry cough was admitted to our hospital. Chest X-ray showed infiltrative shadows and a bulla with a fluid level in the left upper lung field. Bacteriological examination of sputum and bronchoalveolar lavage fluid did not yield any diagnostic results. Percutaneous aspiration of the bulla under fluoroscopy was performed. Bulla with tuberculous infection was considered because a high ADA level was detected in the fluid of the bulla. A culture of the bulla fluid was positive for mycobacterium tuberculosis (TB), which was sensitive to all anti-mycobacterial drugs. The fluid in the bulla gradually increased, and occupied the entire space of the bulla three months later. Percutaneous aspiration of the bulla was performed again and a fluid smear was positive for TB. It was thought that systemic administration of anti-mycobacterial drugs had been ineffective, so percutaneous drainage and subsequent injection of anti-mycobacterial drugs into the bulla was performed. The fluid in the bulla subsequently disappeared and the bulla shrank gradually. Percutaneous drainage of a bulla with tuberculous infection should be considered in those who do not respond to medical management.

[Clinical characteristics of pulmonary embolism without definitive predisposing factors]

Patients with pulmonary embolism may have no definitive predisposing factors for thrombi. The clinical entity of chronic pulmonary embolism is also uncertain. This study clarified the clinical characteristics of pulmonary embolism without definitive predisposing factors. During the last 10 years, 36 consecutive patients were diagnosed as having pulmonary embolism (mean age 61 years, female 75%). Twenty-four patients (67%) had definitive predisposing factors ("definitive" group). Patients without definitive predisposing factors had the following characteristics. The onset of symptoms was out-hospital and insidious. The main symptom was exertional dyspnea without acute episode compatible with an embolism. In four patients (33%) there was a delay of over 2 years form the onset of symptoms to the diagnosis. Three patients had been treated for depression. Thrombolytic therapy caused an inadequate fall in mean pulmonary artery pressure from 41 +/- 11 to 24 +/- 8 mmHg and in three patients it remained over 30 mmHg. Deep vein thrombosis were found in four of nine patients in whom venography were performed 10 days after thrombolytic therapy, but only one patient showed thrombus in the "definitive" group. During the convalescent stage, all patients were treated with prophylactic warfarin. Home oxygen therapy was indicated in three patients and an inferior vena caval filter was implanted in two patients. One third of patients with pulmonary embolism in our institute had no definitive predisposing factors. In these patients, even with thrombolytic therapy, recovery of pulmonary hypertension was often insufficient and deep vein thrombosis persisted. Clinicians should be aware of this disease to avoid undue delay in its diagnosis.

[Two cases of tubercle bacilli infected pulmonary bulla]

Two cases of tubercle bacilli infected bulla are reported. Case 1; A 78-year-old man visited our hospital complaining of fever and chest pain. The chest radiograph revealed the bulla with air fluid level in the left upper lung field. Mycobacterium tuberculosis was detected in the fluid obtained by percutaneous lung aspiration. He was treated with anti-mycobacterial drugs and showed improvement. Case 2; A 66-year-old man visited our hospital complaining of fever, chest pain and dry cough. The chest radiograph revealed the bulla with air fluid level in the left upper lung field. A diagnosis of tubercle bacilli infected bulla was considered because of high level of ADA in the fluid obtained by percutaneous lung aspiration, and anti-mycobacterial drugs were administered. His symptoms were improved and the frequent chest radiograph showed gradual absorption of the fluid. It is suggested that ADA and bacteriological examinations of the fluid obtained by percutaneous lung aspiration are useful for early diagnosis of tubercle bacilli infected bulla.

[Predictors for the massive thrombi occurring in the right coronary artery related to acute myocardial infarction]

Acute myocardial infarction (AMI) related to the right coronary artery (RCA) is associated with a lower reperfusion rate and higher reocclusion rate in the acute phase than AMI related to the left coronary artery. The greater susceptibility of the RCA to development of large thrombi makes successful reperfusion more difficult to achieve. This study investigated predictive factors for massive thrombus in the RCA before the selection of the treatment to achieve better rates of reperfusion. We classified 51 patients with AMI related to RCA into the massive (linear intraluminal radiolucency > 3 cm) thrombus group (9 patients) and the non-massive thrombus group (42 patients). 1) HISTORY: Patients in the massive thrombus group had a greater incidence of hypertension than the non-massive thrombus group, with more left ventricular hypertrophy (p < 0.05). There were no significant differences in other coronary risk factors. 2) RCA morphology: The maximum RCA diameter was significantly greater in the massive thrombus group than that in the non-massive thrombus group [proximal to the right ventricular branch, 4.2 vs 3.2 mm (median); distal to the right ventricular branch, 4.2 vs 3.4 mm, p < 0.05]. 3) Conditions of onset: The elapsed time was significantly longer in the massive thrombus group (15 hours) than that in the non-massive thrombus group (2.5 hours, p < 0.05). More massive thrombus cases were observed in summer (p < 0.05), but there was no evident correlation between massive thrombus formation and the onset time of day, weather, Hct and coagulation factor at the onset, left ventricular ejection fraction or left ventricular end-diastolic pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

[Estimation of respiratory functions by analysis of expired gas and blood gas during artificial ventilation and general anesthesia]

One-hundred and seven patients undergoing elective surgery were studied to analyze the correlations between preoperative spirometric values and respiratory parameters during general anesthesia. They were grouped according to 3 criterions; preoperative %VC of less than 80%, FEV1.0% of less than 70%, V50/V25 exceeding 4.0. Following the induction of general anesthesia and of mechanical ventilation, expiratory flow (VE), FECO2, PaCO2 and PaO2 were measured to calculate respiratory parameters including VCO2-SR, VD/VT-Bohr, VD/VT-physiological (phys), a-ETDCO2, Volume Pressure Index (VPI) and A-aDO2. Six respiratory parameters were compared between the groups, and correlations between preoperative spirometric values were studied. Those with lower %VC had higher values in VCO2-SR and in VPI, and those with lower FEV1.0% had higher values in VCO2-SR, in VD/VT-phys and in a-ETDCO2. Significant correlations were also observed between these parameters. Preoperative V50/V25 and A-aDO2 during general anesthesia did not correlate with any of the parameters studied. We conclude that VCO2-SR, VD/VT-phys, a-ETDCO2 and VPI during general anesthesia are useful to detect the patients with restrictive and/or obstructive lung dysfunction, although they are not sensitive enough to detect those with small airway disease.

Intraaortic balloon pumping as the postangioplasty strategy in acute myocardial infarction

To assess the usefulness of intraaortic balloon pumping (IABP) in acute myocardial infarction (AMI), 114 patients with anterior AMI undergoing emergency percutaneous transluminal coronary angioplasty (PTCA) for total occlusion of the left anterior descending artery were studied. After successful PTCA 66 patients were treated with conventional therapy (group I), and 48 patients were treated with IABP for 25 +/- 8 hours (group II). The reocclusion rate was significantly lower in group II (2.4% vs 17.7% p less than 0.05). An increase in ejection fraction in group II compared with group I was marginally significant (4.5 +/- 12.2% vs 9.2 +/- 13.0%, p = 0.08). Vascular complications occurred in two patients, but there were no deaths from IABP. These results suggest that after successful PTCA for acute myocardial infarction, IABP prevents reocclusion and may add strength to reperfusion in the improvement of left ventricular function.

[A clinical study of the relation between time to reperfusion and infarct size]

Observations made in animal models of reperfusion in acute myocardial infarction have shown that early reperfusion results in myocardial salvage. But the relation between the time of reperfusion and myocardial salvage is not clear in human patients. If earlier reperfusion provides smaller infarct size, reperfusion therapy initiated in the first 1 hour should be the most beneficial. In this study, we compared the results of therapy initiated in the first 1 hour (group A, n = 19) with treatment started 1 to 24 hours after the onset of chest pain (group B, n = 652). The infarct location, development of collateral vessels, number of diseased vessels and reperfusion rate of thrombolysis in the two groups didn't differ. There was a statistically insignificant trend towards total occlusion of the infarct artery in group A (89.5% vs 69.7%, p less than 0.1). Peak CPK and changes in left ventricular ejection fraction (delta EF) were assessed in patients with total occlusion of the left anterior descending artery and successful reperfusion (n = 8 in group A, n = 120 in group B). There was no difference in peak CPK (3281 +/- 2192Iu/l vs 3490 +/- 1811Iu/l) and delta EF (6.3 +/- 17.1% vs 5.8 +/- 11.9%). These findings suggest that there is no relation between the time of reperfusion and myocardial salvage in human patients.

Evaluation of preload reserve during isometric exercise testing in patients with old myocardial infarction: Doppler echocardiographic study

To estimate the preload reserve in response to an increase in afterload in patients with old myocardial infarction, the relation between the Doppler echocardiographic inflow velocity pattern and left ventricular end-diastolic pressure was investigated during isometric handgrip exercise testing. The study population consisted of 16 normal subjects and 40 patients with old myocardial infarction. The 40 patients were subdivided into two groups according to left ventricular end-diastolic pressure at rest: group I (22 patients), less than 18 mm Hg; group II (18 patients), 18 mm Hg or more. At rest, the ratio of peak velocity in atrial contraction phase to peak velocity in early diastolic filling phase (A/E) was significantly higher in the patients with old myocardial infarction than in normal subjects; values in the two subgroups of myocardial infarction did not differ significantly. The A/E ratio and left ventricular end-diastolic pressure increased significantly during exercise in group I. Conversely, the change in left ventricular end-diastolic pressure during exercise in group II was significantly greater than that in group I, and was associated with a decrease in the A/E ratio. Thus, an atrial compensatory mechanism operated effectively in response to the increase in afterload in patients with a normal left ventricular filling pressure, whereas this compensatory mechanism deteriorated in patients with elevated left ventricular filling pressure due to a limited preload reserve.

[Distinctive response of coronary artery compared acute myocardial infarction with angina pectoris associated with angioplasty]

There has been much controversy over the mechanism of successful percutaneous transluminal coronary angioplasty (PTCA). To examine clinical and angiographic factors that might be related to a successful PTCA, we assessed 224 branches treated with emergent or elective angioplasty in evolving acute myocardial infarction (AMI) and angina pectoris (AP). The patients were divided into three groups; group 1 (G1): AP (n = 113), group 2 (G2): AMI with complete obstruction of infarct-related artery (IRA) (n = 79), group 3 (G3): AMI with incomplete obstruction of IRA (n = 32). The morphology of stenotic lesion was classified into smooth type and irregular type. The former shows concentric smooth border, the latter shows eccentric irregular border and multiple irregular border according to the Ambrose classification. Regarding the severity of the stenosis immediately after successful PTCA, there was no significant differences between G2 and G3, however in G1 it was significantly higher than in other groups (G1 vs G2 vs G3, 56% vs 81% vs 78%, p less than 0.001). Irregular type at stenotic lesions before PTCA were present in 72 of 113 branches in G1 vs 60 of 69 in G2 and G3. Regarding the incidence of acute coronary obstruction during PTCA, there was no significant differences between G1 and G2. However, in G3 it was significantly higher than in other groups (G1 vs G2 vs G3, 8% vs 9% vs 38%, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

[The effects of post-ischemic delayed hypoperfusion on the process of recovery of brain function]

The author studied the effect of post-ischemic delayed hypoperfusion on the recovery process of brain function after complete cerebral ischemia in a dog model in which the existence of PDH had been shown previously by the author, using nicardipine as a tool to ameliorate the PDH, the effect of the drug also having been demonstrated by the author in the previous study. Twenty-four dogs underwent 15 min complete cerebral ischemia using aortic clamping method with aorto-atrial bypass formation. EEG (for 16 h) and brain functions, awakening, cranial nerve reflexes, motor functions, behaviors and respiratory functions were evaluated using neurological deficit score (NDS) periodically (for 120 h) after ischemia. Eight dogs (1 microgram group) received nicardipine 1 microgram.kg-1.min-1 for 4 h following 10 micrograms bolus iv injection 5 min after declamping of aorta, another 8 dogs (2 micrograms group) received 10 micrograms + 2 micrograms.kg-1.min-1 nicardipine in the same manner as group 1, and the remaining 8 served as controls. In 1 microgram group the first appearance of EEG activities after ischemia was earlier than control group (41 +/- 11 vs 80 +/- 33 min), and also the appearance rate of alpha waves was higher than the controls (87.5% vs 25%) 16 h after declamping of aorta. NDS scores for awakening, behavior, and respiratory functions were better in 1 microgram than the controls between 36 and 48 h post-ischemia, but there were no significant changes in the scores between the two groups 120 h after ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cerebral hemodynamics of post-ischemic delayed hypoperfusion (PDH) and the effects of nicardipine on the PDH]

Post-ischemic delayed cerebral hypoperfusion (PDH) is considered to be one of the most critical factors limiting brain recovery after cerebral ischemia. This experiment was designed to determine the characteristics of PDH and the effects of nicardipine on the PDH. Twenty-four dogs underwent complete cerebral ischemia for 15 min using aortic clamping method with aorto-atrial bypass formation, and cerebral cortical blood flow (c-CBF), brain stem blood flow (s-CBF), intracranial pressure (ICP), and perfusion pressure (PP) were measured for 48h. Eight dogs (1 microgram group) received nicardipine 1 microgram.kg-1.min-1 for 4 h following 10 micrograms bolus iv injection 5 min after declamping of aorta. Another 8 dogs (2 micrograms group) received 10 micrograms + 2 micrograms.kg-1.min-1 nicardipine in the same manner as in group 1. The remaining 8 served as controls. In the control group c-CBF and s-CBF decreased to 60% and 55% of pre-ischemic values, respectively 1 hour after declamping of aorta, and returned to pre-ischemic values 10 and 6 h later, respectively, in spite of no significant changes in PP's. 1 microgram group and 2 micrograms group maintained pre-ischemic CBF value throughout the experimental period, and the values were significantly higher than in control group between 1st and 5th h post-ischemia. There were no significant differences in ICP's among the 3 groups throughout the experiment. In conclusion, PDH appears to be a phenomenon always accompanying transient complete cerebral ischemia, and it is assumed to be caused by constriction of cerebral vessels. Nicardipine improved PDH, indicating that the underlying mechanism of PDH must be related to a disorder in Ca2+ metabolism of cerebral vessels after ischemia.

[Secundum atrial septal defect in two families]

Two families having secundum atrial septal defect (ASD) were reported. In one family, a 31-year-old male and his 60-year-old mother had secundum ASD without PR prolongation. His 38-year-old brother was diagnosed as having ASD. His grandmother, who had died at the age of 51, was suspected of having congenital heart disease. From early childhood she was noticed to have heart murmur. It was suspected that this was a case of familial ASD without PR prolongation, because it was consistent with the dominant trait of the defect. In the other family, a 16-year-old female had secundum ASD and her 18-year-old brother was also suspected of having ASD. Her 25-year-old brother had been operated on for tetralogy of Fallot, and her sister had died of an unknown congenital heart disease. All of these family members had mental retardation. Her 22-year-old brother was suspected of having a congenital heart disease, because of heart murmur from his early childhood. The parents, who were blood relations (cousins), had neither heart disease nor mental retardation. The children of this family were considered to be cases of congenital heart disease with ASD, associated with mental retardation. It was also suspected that the cause of the defect was a deleterious autosomal recessive gene.

[Clinical features of patients with spontaneous recanalization of the infarct-related artery during evolving acute myocardial infarction]

The clinical features of 124 patients with incompletely obstructed infarct-related arteries during the early stages of myocardial infarction (Group 1) were compared with those of 212 patients having completely occluded coronary arteries (Group 2). Coronary angiography was performed within 12 hours after onset of symptoms in all cases. Patients treated with emergency coronary angioplasty were excluded from the study. Thrombolytic therapy, performed in both groups whenever intracoronary thrombi were detected, was successful in 61% of Group 2. Results were as follows: 1. In Group 1, three-vessel disease was observed more frequently than one-vessel disease (49 vs 27%, p less than 0.005). 2. The peak level of CPK was higher in Group 2 (p less than 0.001), and left ventricular ejection fraction was higher in Group 1 (66 +/- 16 vs 56 +/- 14%, p less than 0.01). 3. Either significant ST elevation or the Q wave was more commonly absent in Group 1 (31 vs 12%, p less than 0.01; 49 vs 12%, p less than 0.001). 4. Improvement of ejection fraction was observed in Group 1, but not in Group 2 even if the infarct-related artery was recanalized within six hours. 5. Extension of an infarct area was more common in Group 1 compared to Group 2 which was successfully treated with thrombolytic therapy (12 vs 3.9%, p less than 0.05). 6. The most important cause of death was extension of an infarct area in Group 1 and pump failure in Group 2, though hospital mortality rates were similar in both groups. It was concluded that patients with myocardial infarction having incompletely obstructed infarct-related coronary arteries have better left ventricular function and higher rates of non-Q myocardial infarction compared with those who had completely obstructed coronary arteries. However, extensions of infarcted areas commonly occur in these patients.

[Effect of isometric hand-grip exercise on left ventricular diastolic filling in patients with effort angina: a pulsed Doppler echocardiographic study]

To detect myocardial ischemia and to estimate cardiac reserve in patients with effort angina pectoris without history of myocardial infarction, left ventricular diastolic filling was measured using Doppler echocardiography during isometric handgrip exercise. Nineteen patients with effort angina pectoris undergoing coronary angiography and 16 normal subjects were studied. The angina patients were categorized in two groups: 12 with single vessel disease (SVD) and seven with multiple vessel disease (MVD). Fifty percent maximum voluntary contraction isometric handgrip exercise was performed for two minutes. 1. The resting A/R in the angina group was significantly greater than that of the normal subjects (SVD: 1.20 +/- 0.24, MVD: 1.21 +/- 0.27, normal 0.85 +/- 0.10) (p less than 0.001). However, the values of many cases in these three groups overlapped. 2. In SVD, the A/R increased significantly during isometric handgrip exercise (1.20 +/- 0.24 to 1.96 +/- 0.66: p less than 0.001). The delta A/R (0.76 +/- 0.15) was significantly greater than that of patients in other groups (MVD: 0.10 +/- 0.13, normal: 0.09 +/- 0.01) (p less than 0.001). Consequently, the A/R after exercise clearly distinguished the SVD from the normal subjects. 3. In MVD, the A/R did not change significantly during exercise (1.21 +/- 0.27 to 1.31 +/- 0.41), and there were no significant differences in delta A/R as compared to the normal subjects (p less than 0.01). The A/R decreased during exercise in three of the seven patients, and this was markedly different from that of the normal subjects. These findings suggest that assessment of changes in left ventricular diastolic filling during isometric handgrip exercise is useful in detecting myocardial ischemia and in estimating cardiac reserve in patients with effort angina pectoris.

Acute myocardial infarction in the elderly

Cardiovascular disease is the most common cause of death in the elderly. In fact, the cardiovascular disease is the number one cause of death in women and the number two cause in men of 65 years or over in Japan. We studied the clinical characteristics and significances of acute myocardial infarction as they relate to the aged.

A new model for total cerebral ischemia in dogs

We have developed a new method producing total cerebral ischemia (TCI) in dogs; clamping ascending aorta with aorto-atrial bypass formation. Clamping ascending aorta provides TCI, the duration of which can be controlled up to the periods of 10 min. Beyond this interval, it is difficult to maintain TCI because of heart failure from high afterload. Blood outflow from left ventricle is completely obstructed except for coronary circulation which is small relative to the blood volume expelled from left ventricle, even if venous return to the heart is reduced. Aorto-atrial bypass formation during aortic clamping provides two distinctive advantages. First, adjusting aortic pressure in an appropriate level low enough not to overload myocardium but still high enough to maintain sufficient coronary blood flow is possible by regulating the blood flow through the bypass tubing, and secondly drug administration and blood volume control is possible through the tubing. These result in better preservation of myocardium, enabling longer TCI and longer survivals after TCI. We were successful in having up to 18 min of TCI with this method. Seventy-five percent of dogs of 12 min TCI and 40% of 15 min TCI survived 7 days, limit of experiment, after TCI, but no dogs of 18 min TCI survived for more than 3 days.

Cerebral blood flow during conventional, new and open-chest cardio-pulmonary resuscitation in dogs

The following parameters were monitored simultaneously in 15 dogs, in order to evaluate the efficacy of conventional CPR (C-CPR), new CPR (N-CPR), and open-chest CPR (O-CPR) on cerebral perfusion: arterial blood pressure (BP), central venous pressure (CVP), intrathoracic airway pressure, blood flow in carotid artery, intracranial pressure (ICP), sagittal sinus blood flow (sinus BF) and pressure (sinus P), and blood flow in cerebral cortex (cortical BF). The sinus blood flow was measured by the direct-method and with a cannulating electromagnetic flowmeter. The cortical blood flow was measured with a termocouple tissue flowmeter. Intracranial pressure was obtained by measuring subarachnoid cerebrospinal fluid pressure. Ventricular fibrillation was induced electrically. Chest compression and ventilation were always done manually in all cardiopulmonary resuscitation. The mean blood pressures during C-CPR, N-CPR and O-CPR were 52, 68 and 95 mmHg, respectively, and mean carotid blood flows per stroke were 36, 71 and 131% of the control values, respectively. The intracranial pressures were 30, 42 and 36 mmHg, respectively, giving the calculated cerebral perfusion pressures (BP-ICP) of 22, 27 and 60 mmHg, respectively. This should have been reflected in cerebral blood flow. Sinus blood flows/min were 18, 18 and 42%, and sinus blood flows per stroke were 55, 45 and 127% of control values, respectively; the differences between C-CPR and N-CPR were not significant. This was also true for cortical blood flow. From this we conclude that, firstly, N-CPR is not significantly better than C-CPR in cerebral perfusion because of its accompanying high intracranial pressure, secondly, O-CPR is far superior to the other two methods in respect of cerebral perfusion.