Mitsuro Kurose

Hemodynamic, renal, and hormonal responses to brain natriuretic peptide infusion in patients with congestive heart failure.

BackgroundThis study was designed to examine the hemodynamic, renal, and hormonal effects of brain natriuretic peptide (BNP) infusion in patients with congestive heart failure (CHF) and in control subjects. Methods and ResultsWe infused synthetic human BNP at a rate of 0.1 ug/kg/min. BNP infusion decreased pulmonary capillary wedge pressure (control, from 5 ± 1 to 2 ± 1 mm Hg, p < 0.01; CHF, from 21 ± 3 to 14 ± 4 mm Hg, p < 0.05) and systemic vascular resistance (control, from 1,264 + 75 to 934 ± 52 dyne · sec · cm−5; CHF, from 2,485 ± 379 to 1,771 ± 195 dyne · sec · cm−5; p < 0.01, respectively) and increased stroke volume index (control, from 49.9 ± 2.7 to 51.5 ± 2.3 ml/m2, p = NS; CHF, from 25.6 ± 3.8 to 32.0 ± 3.9 ml/m2, p < 0.01). BNP infusion significantly increased urine volume (control, from 2.3 ± 0.7 to 7.5 ± 1.9 ml/min; CHF, from 0.8 ± 0.2 to 5.3 ± 1.0 ml/min; p < 0.01, respectively), excretion of sodium (control, from 79.2 + 21.6 to 332.8 ± 70.9 1LEq/min; CHF, from 77.4 ± 20.8 to 753.5 ± 108.0 μEq/min; p < 0.01, respectively), and excretion of chloride (control, from 72.5 ± 18.4 to 256.0 ± 43.3, Eq/min; CHF, from 74.0 + 19.6 to 708.8 ± 103.3 μEq/min; p < 0.01, respectively). Urinary excretion of sodium and of chloride in response to BNP infusion was higher in patients with CHF than in control subjects (p < 0.01, respectively). BNP infusion increased the levels of plasma atrial natriuretic peptide (control, from 65 ± 11 to 84 ± 14 pg/ml; CHF, from 262 ± 65 to 301 ± 62 pg/ml; p < 0.05, respectively) and decreased plasma aldosterone concentrations in both groups (control, from 43.3 ± 12.1 to 27.3 ± 7.1 pg/ml; CHF, from 91.1 ± 34.3 to 66.3 ± 27.2 pg/ml; p < 0.05, respectively). ConclusionsWe conclude that BNP infusion improves left ventricular function in patients with CHF by vasodilation and prominent natriuretic action.

Atrial fibrillation activates platelets and coagulation in a time-dependent manner: A study in patients with paroxysmal atrial fibrillation

OBJECTIVES To determine whether atrial fibrillation (AF) alone affects the fibrinocoagulation system, we examined the relation between fibrinocoagulation activity and duration of AF in patients with paroxysmal AF (PAF). BACKGROUND Patients with chronic AF are at higher risk for stroke and a hypercoagulative state. It is not clear whether this hypercoagulative state is attributable to AF alone or to the underlying disease. There are no reports on the fibrinocoagulation properties in PAF. METHODS Fibrinocoagulation variables in 21 patients with PAF were measured during AF and 7 days after recovery of sinus rhythm. There were positive correlations between the duration of AF and beta-thromboglobulin, platelet factor 4, thrombin-antithrombin III complex and fibrinogen. These variables increased significantly 12 h after the occurrence of PAF; thus, patients were classified into two groups according to the duration of PAF: PAF-I group (< 12 h, n = 10), PAF-II group (> or = 12 h, n = 11). Nine age-matched, healthy subjects formed the control group. RESULTS Levels of beta-thromboglobulin and platelet factor 4 were significantly higher (p < 0.001) by two-way repeated measures analysis of variance (ANOVA), and thrombin-antithrombin III complex and fibrinogen levels tended to be but were not significantly higher (p = 0.06, ANOVA), in the PAF-II group than in the PAF-I group. There were no significant differences between groups in activated partial thromboplastin time, D-dimer or plasmin inhibitor complex. CONCLUSIONS These results indicate that AF itself enhances platelet aggregation and coagulation, which are influenced by the duration of AF. The acceleration of platelet activity and coagulability occurred 12 h after the occurrence of AF.

Emergency extracorporeal life support for patients with near-fatal status asthmaticus

Extracorporeal life support (ECLS) was used to treat three patients with near-fatal status asthmaticus who did not respond to aggressive medical therapies and mechanical ventilation under controlled permissive hypercapnia. ECLS was instituted in patient 1 because PaCO2 was excessively high and pH was excessively low, in patient 2 because hypoxemia and shock were not responsive to treatment, and in patient 3 because of sustained severe hypotension. ECLS supported adequate gas exchange until pulmonary function improved, diminishing the need for mechanical ventilation and preventing pulmonary complications. Pulmonary dysfunction improved markedly after only 21 to 86 hours of ECLS. Aggressive medical treatments were continued during ECLS. Our findings indicate that ECLS is a useful method for preventing death in patients with near-fatal status asthmaticus.

Extracorporeal life support for patients undergoing prolonged external cardiac massage

From November 1987 to February 1992, extracorporeal life support (ECLS) was used for four patients undergoing prolonged external cardiac massage following cardiac arrest. Their underlying diseases consisted of acute pulmonary embolism, pulmonary arterial thrombosis due to protein C deficiency, acute inferior left ventricular infarction accompanied by right ventricular infarction and thoracic contusion. After the initiation of ECLS, hemodynamic variables and metabolic acidosis improved in all of the cases. The case of pulmonary embolism and the case of acute myocardial infarction were successfully weaned from ECLS without complications. They were later discharged ambulatory from the hospital. The patient with pulmonary arterial thrombosis, who was comatose, became alert after the initiation of ECLS. However the patient finally died due to diffuse and massive pulmonary arterial thrombosis, which was probably related to protein C deficiency. The patient with thoracic contusion was also comatose before ECLS. He did not recover from the coma and died soon after the disconnection of ECLS. The latter two cases were suspected to have had irreversible organ failures not responsive to mechanical support of both circulation and respiration. We conclude that ECLS is a very useful method for patients requiring prolonged cardiac massage following cardiac arrest.

Atrial natriuretic polypeptide is removed by the lungs and released into the left atrium as well as the right atrium in humans

To examine the sites of release and removal of plasma atrial natriuretic polypeptide plasma levels in the femoral vein, right atrium, pulmonary artery, pulmonary capillary bed, left atrium and aortic root were measured in 11 control subjects and 22 patients with mitral stenosis. Mean plasma natriuretic polypeptide levels in the femoral vein, right atrium, pulmonary artery, pulmonary capillary bed, left atrium and aortic root were, respectively, 64 +/- 29, 124 +/- 72, 103 +/- 44, 83 +/- 30, 106 +/- 46 and 101 +/- 35 pg/ml in the control subjects and 321 +/- 170, 500 +/- 234, 458 +/- 266, 356 +/- 209, 434 +/- 222 and 432 +/- 217 pg/ml in the patients with mitral stenosis. In both the control subjects and the patients with mitral stenosis, there was a significant increase between the femoral vein and the right atrium and between the pulmonary capillary bed and the left atrium and a significant decrease between the pulmonary artery and the pulmonary capillary bed. Blood samples were also taken simultaneously from the pulmonary vein and the pulmonary capillary bed, as well as from the pulmonary artery and the left atrium, in 25 patients (11 control subjects, 5 patients with mitral stenosis and 9 patients with atrial septal defect). There was no difference in plasma atrial natriuretic polypeptide levels between the pulmonary capillary bed and the pulmonary vein in these 25 patients. It is concluded that atrial natriuretic polypeptide 1) is released into the left as well as the right atrium, and 2) is removed by the lungs.

The determinant of severe cerebral dysfunction in patients undergoing emergency extracorporeal life support following cardiopulmonary resuscitation

We investigated the factors associated with cerebral dysfunction in patients undergoing extracorporeal life support (ECLS) following conventional advanced cardiac life support (ACLS). The subjects were 9 patients in whom ECLS was started following ACLS because of intractable cardiac arrest. We investigated whether the irreversibility of cerebral dysfunction during ECLS was related to the cardiopulmonary resuscitation (CPR) time, arterial pH and blood gases, hemoglobin concentration (Hb), peak arterial pressure (PAP) before the start of ECLS and total doses of epinephrine and sodium bicarbonate administered during CPR. Two of the 3 patients who recovered consciousness were weaned from ECLS and survived, while all 6 patients who did not recover from coma were not weaned and died. There was no difference in the CPR time, Hb and PAP before the start of ECLS along with total doses of epinephrine and sodium bicarbonate administered during CPR between the patients who recovered consciousness and those who did not. In addition, there was no difference in arterial pH and blood gases except the arterial oxygen tension (PaO2) between the groups. The PaO2 values before the start of ECLS in the patients who remained in coma ranged from 34 to 58 mmHg, whereas those in the patients who recovered consciousness ranged from 132 to 442 mmHg. The PaO2 values before the start of ECLS in the patients who remained in coma were less than 60 mmHg, whereas those in the patients who recovered consciousness were over 60 mmHg. The present study suggests that hypoxemia during CPR may play a major role in severe cerebral dysfunction in patients undergoing ECLS and PaO2 during CPR.

Prolonged artificial liver support in a child with fulminant hepatic failure

In Japan, liver transplantation from brain dead donors has not yet started. The authors present the first report of a clinical experience with a child with fulminant hepatic failure in whom the combined treatment of plasma exchange and continuous hemodiafiltration using a high-performance polymethylmethacrylate membrane was used successfully to sustain life for a period of as long as 54 days before liver transplantation from a living donor could be performed. The combination of plasma exchange and continuous hemodiafiltration appeared to maintain blood coagulation and level of consciousness effectively. Although the combined use of plasma exchange and continuous hemodiafiltration is still unsatisfactory as an artificial liver support, the authors suggest that this technique may be useful to support the life of a child who awaits liver transplantation. ASAIO Journal 1996; 42:233–235.

Reduced cardiac extraction of norepinephrine and epinephrine in patients with heart failure - correlation with left ventricular function

To assess whether the impairment of neuronal norepinephrine (NE) uptake is involved in the increased NE release observed in the failing heart, we examined the cardiac extractions of NE and epinephrine (E) and their correlation with left ventricular function in 16 patients with anterior transmural old myocardial infarction (OMI) and 18 patients with dilated cardiomyopathy (DCM). The plasma NE and E levels were both increased in OMI and DCM, particularly in the coronary sinus, as compared with those in 16 control subjects (Control). The cardiac NE and E extractions were significantly reduced in OMI (P < 0.001) and in DCM (P < 0.001) as compared with those in the Control (NE: -38 +/- 36% in OMI, -33 +/- 28% in DCM, and 14 +/- 18% in Control; E: 30 +/- 12% in OMI, 32 +/- 17% in DCM, and 54 +/- 8% in Control). However, there was no reduction in the NE and E extraction in the leg in OMI and DCM. Cardiac NE and E extractions both showed significant correlation with the left ventricular ejection fraction (r = 0.685, P < 0.001 and r = 0.609, P < 0.001, respectively). We conclude that, in patients with heart failure, NE release from the heart is increased partially due to the reduction of the cardiac neuronal uptake of NE which is proportional to the severity of left ventricular dysfunction.

Prognosis of critically ill patients with multiple organ failure.

The purpose of this study was to determine the mortality rate in 527 critically ill patients with multiple organ failure (MOF), treated in our ICU between August, 1986 and January, 1992, and to compare it with the results obtained in a group of patients studied who had been treated between October, 1978 and July, 1986. The relationship between the mortality rate and each type of organ failure and the extent of organ system involvement was also investigated. The overall mortality rate was 25%, and the rate increased with the number of failed organs. Sepsis and disseminated intravascular coagulation were closely associated with the development of MOF. The mortality rate of patients with the failure of two organs in the present study was significantly lower than that found in those in the previous study. Although artificial organ mechanical life support technology other than that for patients with renal failure is still unsatisfactory, these results suggest that the prognosis of patients with MOF is improving.

Emergency and long-term extracorporeal life support following acute myocardial infarction: Rescue from severe cardiogenic shock related to stunned myocardium

There has been no report regarding therapy of extracorporeal life support (ECLS) that showed stunned myocardium echocardiographically and electrocardiographically in patients with acute myocardial infarction. ECLS was performed in eight patients with cardiogenic shock or arrest unresponsive to catecholamines and intra-aortic balloon pumping following myocardial infarction; these patients required prolonged external cardiac massage. After the initiation of ECLS, both blood pressure and metabolic acidosis improved in all patients. Four of eight patients were weaned from ECLS after a mean of 69.3 h, which was far longer than previously reported in patients with ischemic heart disease. Three of these patients survived, and cardiac function recovered to NYHA class II in two of the survivors and class III in the other. The other five patients did not recover from coma during ECLS and died. A marked improvement of ventricular wall motion was seen in two survivors with the disappearance of pathologic Q waves after the initiation of ECLS. No occlusion of the coronary arteries or bypass grafts was observed in any of the survivors. These findings suggested the existence of stunned myocardium with myocardial reperfusion. The recovery of stunned myocardium may be delayed for days or even weeks, hence the extended period of ECLS therapy was theoretically justifiable. We conclude that long-term ECLS is a useful therapeutic method for patients with severe cardiogenic shock that is related to stunned myocardium.