Torsade de pointes as a complication of subarachnoid hemorrhage: a critical reappraisal

Evaluation of index of cardiac-electrophysiological balance in patients with subarachnoid hemorrhage

Background

Various electrocardiographic (ECG) changes occur after subarachnoid hemorrhage (SAH). Prolonged QT and corrected QT (QTc) intervals are notable changes. QT, QTc, T peak-to-end T(p-e) intervals, and Tp-e/QTc ratio are used as ventricular arrhythmia indices. In recent publications, the cardiac electrophysiological balance index (ICEB), which provides more information than other ECG parameters (QT, QTc, etc.), is recommended in predicting the risk of ventricular arrhythmia. This study aims to assess ICEB in aneurysmal SAH patients.

Methods

The study included 50 patients diagnosed with aneurysmal SAH and 50 patients diagnosed with hypertension without end-organ damage as the control group. All patients’ Fisher scores and Glasgow Coma Scale (GCS) scores were recorded. Both groups were given 12-lead ECGs. QT, QTc, Tp-e intervals, QRS duration, ICEB (QT/QRS), ICEBc (QTc/QRS), and T(p-e)/QTc values were calculated and analyzed between groups.

Results

Compared to the control group; QT (426,64 ± 14,62 vs. 348,84 ± 12,24 ms, p < 0,001), QTc (456,24 ± 28,84 vs. 392,48 ± 14,36 ms, p < 0,001), Tp-e (84,32 ± 3,46 vs. 70,12 ± 3,12, p < 0,001), Tp-e/QTc (0,185 ± 0,08 vs. 0,178 ± 0,02, p < 0,001), ICEB (4,53 ± 0,78 vs. 3,74 ± 0,28, p < 0,001) and ICEBc (4,86 ± 0,86 vs. 4,21 ± 0,24, p < 0,001) were significantly higher in patients with aneurysmal SAH. QT, QTc and Tp-e interval, Tp-e/QTc ratio, ICEB (QT/QRS) and ICEBc (QTc/QRS) were positively correlated with the Fisher score and were negatively correlated with the GCS. According to linear regression analyses, the ICEBc (QTc/QRS) found to be independently associated with the Fisher score.

Conclusion

The values of the ICEB and ICEBc were significantly increased in patients with aneurysmal SAH. The severity of SAH was positively correlated with the ICEB and ICEBc. The ICEBc (QTc/QRS) independently associated with the Fisher score. This may that SAH suggest may predispose to malignant ventricular arrhythmias.

Subarachnoidal hemorrhage related cardiomyopathy: an overview of Tako-Tsubo cardiomyopathy and related cardiac syndromes

INTRODUCTION

Subarachnoid hemorrhage (SAH) is caused by a ruptured intracranial aneurysm leading to acute extravasation of blood into the subarachnoid space. SAH has an incidence of 6.3 per 100,000 persons per year in Europe and accounts for 5% of all strokes. SAH occurs at a relatively young age and has poor clinical outcomes and high mortality rates. Cardiac syndromes are regularly seen in patients with acute neurologic disease including SAH. These cardiac complications of SAH are associated with increased morbidity and mortality and present in a large variety and severity.

AREAS COVERED

The main goal of this review is to describe the SAH-related cardiac syndromes. Secondly, we will provide an overview of the underlying pathophysiology regarding the development of cardiac syndromes. Thirdly, we will describe the impact of cardiac syndromes on patient outcome.

EXPERT OPINION

Of all neurology patients, SAH patients have the highest risk of developing takotsubo syndrome (TTS), occurring in about 0.8-30% of patients. Both TTS and neurogenic stunned myocardium have many similarities on echocardiographic evaluation. In European Cardiology consensus, SAH is recognized as a primary cause of TTS.

Thoracic sympathetic nuclei ischemia: Effects on lower heart rates following experimentally induced spinal subarachnoid hemorrhage

BACKGROUND

The neuropathological mechanism of heart rhythm disorders, following spinal cord pathologies, to our knowledge, has not yet been adequately investigated. In this study, the effect of the ischemic neurodegeneration of the thoracic sympathetic nuclei (TSN) on the heart rate (HR) was examined following a spinal subarachnoid hemorrhage (SSAH).

METHODS

This study was conducted on 22 rabbits. Five rabbits were used as a control group, five as SHAM, and twelve as a study group. The animals' HRs were recorded via monitoring devices on the first day, and those results were accepted as baseline values. The HRs were remeasured after injecting 0.5 cc of isotonic saline for SHAM and 0.5 cc of autolog arterial blood into the thoracic spinal subarachnoid space at T4-T5 for the study group. After a three-week follow-up with continuous monitoring of their HRs, the rabbit's thoracic spinal cords and stellate ganglia were extracted. The specimens were evaluated by histopathological methods. The densities of degenerated neurons in the TSN and stellate ganglia were compared with the HRs.

RESULTS

The mean HRs and mean degenerated neuron density of the TSN and stellate ganglia in control group were 251±18/min, 5±2/mm³, and 3±1/mm³, respectively. The mean HRs and the mean degenerated neuron density of the TSN and stellate ganglia were detected as 242±13/min, 6±2/mm³, and 4±2/mm³ in SHAM (P>0.05 vs. control); 176±19/min, 94±12/mm³, and 28±6/mm³ in the study group (P<0.0001 vs. control and P<0.005 vs. SHAM), respectively.

CONCLUSIONS

SAH induced TSN neurodegeneration may have been responsible for low HRs following SSAH. To date this has not been mentioned in the literature.

Polymorphic Ventricular Tachycardia Secondary to Subarachnoid Haemorrhage: A Rare Occurrence in the Setting of Normal QTc

Subarachnoid hemorrhage (SAH) is a neurologic emergency associated with high mortality rate. Polymorphic ventricular tachycardia (VT) is a rare arrhythmia. It can occur in any setting of a long QT interval and bradycardia. This may result from a cardiomyopathy (both ischemic and non-ischemic), acute coronary ischemia, congenital long QT syndrome, electrolyte disturbances and cerebrovascular diseases. We report a rare case of polymorphic VT of unclear etiology with a normal corrected QT, likely secondary to SAH. Reports associating ventricular arrhythmias and SAH have been described, yet the mechanism of this association remains unclear. Previous observations of VT seen in patients with SAH suggest a relationship with QT prolongation. The QT interval, however, remained normal in our patient, suggesting an alternative and unknown mechanism for the polymorphic VT.

Electrocardiographic Abnormalities Predict Adverse Clinical Outcomes in Patients with Subarachnoid Hemorrhage

BACKGROUND

We conducted a retrospective cohort study of a large sample to assess whether electrocardiographic (ECG) abnormalities are independently associated with the occurrence of neurogenic pulmonary edema (NPE), delayed cerebral ischemia (DCI), and in-hospital death after nontraumatic subarachnoid hemorrhage (SAH).

METHODS

In this retrospective observational study, patients who were admitted within 72 hours of SAH symptom onset between 2013 and 2015 were enrolled. Twelve-lead ECG findings obtained within 72 hours after SAH and the presence of NPE, DCI, and in-hospital death were collected based on the results reported in the medical records.

RESULTS

We included 834 patients. NPE occurred in 192 patients (23%). The median delay from SAH onset to NPE was 3 days (interquartile range [IQR]: 5 days). DCI occurred in 223 patients (27%; median delay to DCI, 4 days; IQR: 5 days). In total, 141 patients (17%) died in the hospital (median time to death, 12 days; IQR: 18 days). The frequency of ECG abnormalities for all enrolled patients was 65%. Corrected QT prolongation had an adjusted risk ratio (RR) of 1.5 (1.1-2.2) for NPE and 1.8 (1.3-2.4) for DCI. ST depression had an adjusted RR of 3.0 (1.2-7.5) for in-hospital death. NSSTTCs (nonspecific ST- or T-wave changes) had an adjusted RR of 2.7 (1.8-4.2) for NPE, 2.8 (1.9-4.3) for DCI, and 2.2 (1.3-3.5) for in-hospital death. All RRs were adjusted for age and Hunt-Hess scores.

CONCLUSIONS

ECG abnormalities assessed within 72 hours after SAH using a standard 12-lead ECG are independently associated with an increased risk of adverse clinical outcomes in patients with nontraumatic SAH.

Cardiac damage after subarachnoid hemorrhage

Patients who had no heart disease had T-wave inversion and prolongation of the QT interval in electrocardiogram after Subarachnoid hemorrhage (SAH), which was reported 70years before. Cardiac complications, including focal myocytolysis, electrocardiographic changes, arrhythmias and left ventricular wall motion abnormalities and pulmonary edema. The autonomic and cardiovascular effects of SAH, however, are modulated by concomitant factors such as pre-existent cardiac diseases, electrolyte disorders and, probably, by genetic alterations in the ionic control of myocyte repolarization. Although beta-blockers have been reported to prevent myocardial damage following SAH, adequate clinical trials are lacking, and the widespread use of these drugs in acute cerebrovascular disease is not supported by evidence. Cardiac injury occurs frequently after SAH, and the most widely investigated form of neurocardiogenic injury.

Neurogenic stunned myocardium

Neurogenic stunned myocardium may be defined as myocardial injury and dysfunction occurring after diverse types of acute brain injury as a result of imbalance of the autonomic nervous system. The spectrum of observed cardiac abnormalities includes electrocardiographic changes, arrhythmia, myocardial necrosis, release of B-type natriuretic peptide, and both systolic and diastolic dysfunction of the left ventricle. These are reversible abnormalities, and although management should include careful cardiac monitoring, treatments should generally focus on the underlying neurologic process to maximize neurologic recovery.

Ventricular arrhythmia risk after subarachnoid hemorrhage

INTRODUCTION

Cardiac morbidity and mortality after aneurysmal subarachnoid hemorrhage (SAH) are attributable to myocardial injury, decreased ventricular function, and ventricular arrhythmia (VA). Our objective was to test the relationships between QTc prolongation, VA, and survival after SAH.

METHODS

In 200 subjects with acute aneurysmal SAH, electrocardiograms, echocardiograms, and telemetry were evaluated. Serum electrolytes and troponin were also evaluated.

RESULTS

Initial QTc (mean 460 +/- 45 ms) was prolonged (> or = 470 ms) in 38% of subjects and decreased on follow-up (469 +/- 49 initial vs. 435 +/- 31 ms follow-up; N = 89; P < 0.0001). VA was present in 14% of subjects, 52% of subjects with VA had QTc > or = 470 ms, and initial QTc trended toward longer duration in subjects with VA (474 +/- 61 vs. 457 +/- 42 ms; P = 0.084). Multivariate analysis demonstrated significant predictors of VA after SAH were increasing age (OR 1.3/5 years; P = 0.025), increasing stroke severity (OR 1.8; P = 0.009), decreasing heart rate (OR 0.5/10 beats/min; P = 0.006), and the absence of angiotensin converting enzyme inhibitor or angiotensin II receptor antagonist use at SAH onset (OR 0.10; P = 0.027). All-cause mortality was 19% (25/135) at 3 months and subjects with VA had significantly higher mortality than those without VA (37% vs. 16%; P = 0.027).

CONCLUSIONS

These data demonstrate that QTc prolongation and arrhythmias are frequently noted after SAH, but arrhythmias are often not associated with QTc prolongation. In addition, the presence of VA identified subjects at greater risk of mortality following their SAH.

Development of torsade de pointes caused by exacerbation of QT prolongation during clipping of cerebral artery aneurysm in a patient with subarachnoid haemorrhage

We report the case of a 79-yr-old woman with subarachnoid haemorrhage (SAH) in whom torsade de pointes (TdP) caused by worsening the QT prolongation occurred during clipping of cerebral artery aneurysm. This patient shows a potential risk of occurrence of life-threatening tachyarrhythmia, TdP by prolonging the QT interval during surgery in patients with SAH even with no additional factors that predispose to TdP. Therefore, a proper monitoring of the QT interval is necessary as a predictor of TdP. When ventricular tachyarrhythmia occurs, recognition of TdP is important because antiarrhythmic drug therapy for TdP is different from that for ventricular tachyarrhythmias that is not TdP.

QTc dispersion in children with severe head trauma

OBJECTIVE

Corrected QT (QTc) interval prolongation has been described after subarachnoid hemorrhage and head injury in adults. Abnormal QTc prolongation is associated with a higher risk of ventricular arrhythmias. The aim of this study was to analyze QTc interval and QTc dispersion in children with severe head trauma.

METHODS

Forty-three patients with severe head trauma and 49 children with no or only mild head injury as controls were enrolled in the study. QT interval from standard 12-lead electrocardiogram immediately after admission was calculated. QT interval was corrected by heart rate according to Bazett formula, and then QTc dispersion was calculated. At the same time, levels of serum electrolytes were measured.

RESULTS

Although no significant difference in terms of age, sex, and R-R interval was found, QTc interval and QTc dispersion values were significantly increased in the patients with severe head trauma compared with those with no or only mild head injury (QTc, 447 +/- 31 vs. 409 +/- 27 milliseconds; QTc dispersion, 77 +/- 22 vs. 52 +/- 16 milliseconds, respectively). When the patients with severe head trauma were categorized as those with or without intracranial hemorrhage, both QTc interval and QTc dispersion were significantly greater in those with intracranial hemorrhage. These electrocardiographic parameters were inversely associated with Glasgow Coma Scale score, serum calcium levels, and, at a lesser degree, potassium levels.

CONCLUSIONS

Children with severe head trauma, especially those with intracranial hemorrhage have longer QTc interval and greater QTc dispersion.

Spontaneous subarachnoid hemorrhage and serious cardiopulmonary dysfunction--a systematic review

INTRODUCTION

: The association between the degree of neurological deficit and cardiopulmonary dysfunction in patients with spontaneous subarachnoid hemorrhage (SAH) is poorly understood.

METHOD

A systematic search (MEDLINE, bibliographies, to 9.2004) was performed for prospective studies (any architecture; > or = 10 patients with SAH), reporting on neurological deficit and cardiopulmonary dysfunction. Neurological deficit was graded according to the Hunt-Hess or Botterell scores as minimal (1 or 2 points), moderate (3), or severe (4 or 5), and tested for an association with cardiopulmonary dysfunction (Chi-square test).

RESULTS

Relevant data came from two randomized trials, four case control studies, and 31 uncontrolled series. In eight studies (386 patients), ECG abnormalities were found in 32% of patients with minimal, 55% with moderate, and 58% with severe neurological deficit (P < 0.0001). In six studies (135), echocardiographic abnormalities were found in 4% of patients with minimal, 30% with moderate, and 52% with severe neurological deficit (P = 0.0001). In two trials (63), creatinine phosphoskinase was increased in 18% of patients with minimal, 71% with moderate, and 100% with severe neurological deficit (P < 0.0001). In three trials (309), troponin-I was increased in 10% of patients with minimal, 20% of patients with moderate, and 46% with severe neurological deficit (P < 0.0001). In five trials (163), pulmonary edema was found in 4% of patients with minimal, 12% with moderate, and 35% with severe neurological deficit (P < 0.0001). Seventeen studies reported on mortality; 26% of the patients died, 80% of deaths were directly related to SAH.

CONCLUSIONS

In patients with spontaneous SAH, cardiopulmonary dysfunction is more likely to occur with increasing neurological deficit.

Traumatic subarachnoid hemorrhage and QTc prolongation

OBJECTIVE

Spontaneous subarachnoid hemorrhage (SAH) causes a prolonged corrected QT interval (QTc) in 25% to 90% of patients, but whether this occurs with traumatic SAH (tSAH) is unknown. This investigation was conducted to determine whether QTc prolongation occurs with tSAH and to evaluate QTc prolongation with respect to severity of tSAH.

DESIGN

Records of 104 consecutive tSAH patients were reviewed. A QTc was calculated on posttrauma day (PTD) 0, 1, and 3. Cranial computed tomography (CT) scans were graded for severity using a previously validated scale. QTc intervals were compared based on CT scan severity.

SETTING

Pennsylvania level II trauma center.

PATIENTS

Trauma patients with tSAH.

INTERVENTIONS

None

MEASUREMENTS AND MAIN RESULTS

QTc prolongation occurred in 67% of those with tSAH. Mean QTc intervals for PTD0, PTD1, and PTD3 were 470 +/- 69 ms, 467 +/- 72 ms, and 465 +/- 50 ms, respectively. As the severity of the tSAH increased, the average QTc became more prolonged (Pearson's r = 0.855, P = 0.003).

CONCLUSIONS

tSAH is a common cause of an acquired prolonged QTc syndrome. As the tSAH becomes more severe, the QTc becomes more prolonged.

Multivariate analysis of risk factors for QT prolongation following subarachnoid hemorrhage

BACKGROUND

Subarachnoid hemorrhage (SAH) often causes a prolongation of the corrected QT (QTc) interval during the acute phase. The aim of the present study was to examine independent risk factors for QTc prolongation in patients with SAH by means of multivariate analysis.

METHOD

We studied 100 patients who were admitted within 24 hours after onset of SAH. Standard 12-lead electrocardiography (ECG) was performed immediately after admission. QT intervals were measured from the ECG and were corrected for heart rate using the Bazett formula. We measured serum levels of sodium, potassium, calcium, adrenaline (epinephrine), noradrenaline (norepinephrine), dopamine, antidiuretic hormone, and glucose.

RESULTS

The average QTc interval was 466 +/- 46 ms. Patients were categorized into two groups based on the QTc interval, with a cutoff line of 470 ms. Univariate analyses showed significant relations between categories of QTc interval, and sex and serum concentrations of potassium, calcium, or glucose. Multivariate analyses showed that female sex and hypokalemia were independent risk factors for severe QTc prolongation. Hypokalemia (<3.5 mmol/l) was associated with a relative risk of 4.53 for severe QTc prolongation as compared with normokalemia, while the relative risk associated with female sex was 4.45 as compared with male sex. There was a significant inverse correlation between serum potassium levels and QTc intervals among female patients.

CONCLUSION

These findings suggest that female sex and hypokalemia are independent risk factors for severe QTc prolongation in patients with SAH.

Prevalence of male and female patterns of early ventricular repolarization in the normal ECG of males and females from childhood to old age

OBJECTIVES

This study was designed to establish the cause of electrocardiographic (ECG) pattern differences between genders.

BACKGROUND

The male and female patterns of early ventricular repolarization in normal ECGs differ from each other. The male pattern displays a higher J-point amplitude and increased ST angle. The distribution of these patterns between genders has not been studied.

METHODS

Normal ECGs of 529 males and 544 females, age 5 to 96 years, were subdivided into nine age groups in each gender. We designated the pattern as female if the J point was <0.1 mV in each of the leads V(1) to V(4), and as male if the J point was > or =0.1 mV and the ST angle > or =20 degrees in at least one of the V(1) to V(4) leads; the pattern was indeterminate if the J point was > or =0.1 mV and the ST angle was <20 degrees.

RESULTS

Distribution of patterns was significantly different between genders (p < 0.001). In females, the patterns were distributed similarly from puberty to advanced age with about 80% prevalence of the female pattern. In males, the male pattern prevalence increased at puberty, reached 91% in the age group of 17 to 24 years and declined gradually with advancing age to 14% in the oldest males. The prevalence of indeterminate pattern was about 10% in both genders. Patterns were unchanged in 95% of 493 subjects who had ECGs recorded at separate times or at different heart rates.

CONCLUSIONS

Gender differences in early ventricular repolarization were caused by age-dependent changes in prevalence of the male pattern.

Torsades de pointes: unanswered questions

Torsade de pointes (Tdp) is a polymorphic ventricular tachycardia (VT) in which the axis of the QRS complex changes direction after a certain number of complexes as if the complex rotated around the baseline. Tdp is usually associated with QT prolongation, and dispersion of ventricular repolarlization (DR). Experimental models of tdp are usually associated with induction of early after depolarizations (EADs). Several aspects of the pathogenesis of tdp are incompletely understood. The purpose of this article is to propose the directions in research that may increase our current understanding of the factors responsible for tdp. The most plausible hypotheses requiring further supporting evidence are: 1. The occurrence of tdp requires the presence of DR i.e. tdp does not occur in the absence of DR. 2. EADs appear to play an important role as a trigger to tdp in the animal models, but more evidence are needed at the clinical level. 3. EADs may be responsible for arrhythmias other than tdp. 4. The greater incidence of tdp in the females than in tha males may be attributed to differences in the duration of the QT interval and different morphology of the ST-segment and the T-wave. The above gender differences may be caused by the effects of gonadal hormones which modulate some of the membrane currents flowing during early ventricular repolarization.

Long QT syndrome: diagnosis and management

BACKGROUND

Long QT syndrome (LQT) is characterized by prolongation of the QT interval, causing torsade de pointes and sudden cardiac death. The LQT is a disorder of cardiac repolarization caused by alterations in the transmembrane potassium and sodium currents. Congenital LQT is a disease of transmembrane ion-channel proteins. Six genetic loci of the disease have been identified. Sporadic cases of the disease occur as a result of spontaneous mutations. The acquired causes of LQT include drugs, electrolyte imbalance, marked bradycardia, cocaine, organophosphorus compounds, subarachnoid hemorrhage, myocardial ischemia, protein sparing fasting, autonomic neuropathy, and human immunodeficiency virus disease.

METHODS

Data on the diagnosis and management of LQT were thoroughly reviewed.

RESULTS AND CONCLUSIONS

The diagnosis of LQT primarily rests on clinical and electrocardiographic features and family history. The clinical presentations range from dizziness to syncope and sudden death. Genetic screening is available primarily as a research tool. Short-term treatment of LQT is aimed at preventing the recurrences of torsades and includes intravenous magnesium and potassium administration, temporary cardiac pacing, withdrawal of the offending agent, correction of electrolyte imbalance, and, rarely, intravenous isoproterenol administration. The long-term treatment is aimed at reducing the QT-interval duration and preventing the torsades and sudden death and includes use of oral beta-adrenergic blockers, implantation of permanent pacemaker/cardioverter-defibrillator, and left thoracic sympathectomy. Sodium channel blockers are promising agents under investigation. Electrocardiograms are recorded for screening of family members. The data favor treating asymptomatic patients, if <40 years old at the time of diagnosis, with beta-adrenergic blockers.

Clinical and therapeutic aspects of congenital and acquired long QT syndrome

The long QT syndrome is characterized by prolongation of the corrected QT (QTc) interval on the surface electrocardiogram. It is associated with precipitation of a polymorphic ventricular tachycardia, torsade de pointes, which may cause sudden death. The syndrome is a disorder of cardiac repolarization caused by the alterations in the transmembrane potassium and sodium currents. Six genetic loci for the congenital forms of the syndrome have been identified; sporadic cases occur because of spontaneous mutations. Acquired causes of the long QT syndrome include drugs, electrolyte imbalance, toxins, marked bradycardia, subarachnoid hemorrhage, stroke, myocardial ischemia, protein-sparing fasting, autonomic neuropathy, and human immunodeficiency virus disease. Clinical symptoms are the result of the precipitation of torsade de pointes and range from such minor symptoms as dizziness to syncope and sudden death. Short-term treatment is aimed at preventing the recurrences of torsade de pointes and includes intravenous magnesium and potassium administration, temporary cardiac pacing, and correction of electrolyte imbalance; rarely, intravenous isoproterenol is indicated. Long-term management includes use of beta-blockers, permanent pacemaker placement, and cardioverter-defibrillator implantation. Asymptomatic patients are treated if under the age of 40 years at the time of diagnosis.

QT dispersion. Is it an independent risk factor for in-hospital mortality in patients with intracerebral hemorrhage?

Electrocardiographic repolarization changes, comprising QT prolongation, are most commonly seen after intracerebral hemorrhage. In this study in patients with intracerebral hemorrhage (ICH), QT dispersion and its daily changes were examined and the relation between QT dispersion and in-hospital mortality assessed. In 28 patients with intracerebral hemorrhage, diagnosed by computerized tomographic scanning, an ECG was obtained on the day of admission to hospital and then serial ECGs were recorded on the following four consecutive days. Blood electrolytes (K, Ca, Mg) were also analysed. The patients with intracerebral hemorrhage were followed until discharge or death (mean 14 +/- 4 days). QT, QT peak, and QT-QT peak dispersion were measured on simultaneous twelve lead electrocardiograms. Also, in 29 healthy subjects as a control group, five consecutive day serial electrocardiograms were recorded. There were no statistically significant differences between the study and control groups in terms of gender and age. During the five days, QT, QT peak, and QT-QTpeak dispersion values were significantly higher in patients with intracerebral hemorrhage than in the control subjects (p < 0.001). There were no statistically significant differences in two patient groups with intracerebral hemorrhage who died and who were discharged in terms of mean QT, QTpeak, and QT-QTpeak dispersion values. In conclusion, QT, QT peak, and QT-QTpeak dispersion values were significantly greater in patients with intracerebral hemorrhage than in the control subjects, but QT, QT peak, and QT-QT peak dispersions were not independent risk factors for in-hospital mortality in patients with intracerebral hemorrhage.