Two Distinct Responses of Left Ventricular End-Diastolic Pressure to Leg-Raise Exercise in Euvolemic Patients with Exertional Dyspnea

BACKGROUND AND OBJECTIVES: Few studies have invasively assessed diastolic functional reserve and serial changes in left ventricular hemodynamics in euvolemic patients with exertional dyspnea. In this study, sequential changes in left ventricular end-diastolic pressure (LVEDP) to leg-raise exercise were measured invasively in patients with early heart failure with preserved ejection fraction (HFpEF) to determine the association between these serial changes and echocardiographic results or clinical features. SUBJECTS AND METHODS: During their hospital stay, 181 patients with early HFpEF underwent left cardiac catheterization, coronary angiography, and transthoracic echocardiography (TTE). Leg-raise exercise was performed in two stages: during cardiac catheterization and again during TTE. RESULTS: Compared with the initial values, all the invasively measured LVEDP values increased significantly during the leg-raise exercise, whereas the septal e/e' ratio remained unchanged. Active leg-raise led to increased LVEDP, which caused dyspnea. The severity of symptoms correlated with the level and extent of changes in LVEDP. At the end of active leg-raise, LVEDP decreased in 40 patients (22.1%), who were younger and had significantly lower e/e' ratios. On multivariate analysis to predict the response of LVEDP to active leg-raise, age and the septal e/e' ratio remained significant predictors. CONCLUSION: Despite having similar LVEDP values at rest, patients may respond to exercise with different LVEDP levels and clinical manifestations, depending on their diastolic capacity. The leg-raise exercise in early HFpEF can elucidate individual diastolic profiles, and the LVEDP response to the leg-raise test may serve as a useful criterion in stratifying patients with early HFpEF with respect to functional reserve.

Higher Blood Pressure Variability in White Coat Hypertension; from the Korean Ambulatory Blood Pressure Monitoring Registry

BACKGROUND AND OBJECTIVES: Blood pressure variability (BPV) was recently shown to be a risk factor of stroke. White coat hypertension (WCH) used to be regarded as innocuous, but one long-term follow-up study reported that WCH increased stroke rate compared to normotension (NT). In this study, we aimed to evaluate the relationship between WCH and BPV. SUBJECTS AND METHODS: We analyzed 1398 subjects from the Korean Ambulatory Blood Pressure Registry, who were divided into NT (n=364), masked hypertension (n=122), white coat hypertension (n=254), and sustained hypertension (n=658) groups. RESULTS: Baseline characteristics were similar among groups. The average real variability (ARV), a highly sensitive BPV parameter, was highest in the WCH group, followed by the sustained hypertension, masked hypertension, and NT groups. The results persisted after being adjusted for covariates. The WCH vs. sustained hypertension results (adjusted mean±standard error) were as follows: 24-h systolic ARV, 22.9±0.8 vs. 19.4±0.6; 24-h diastolic ARV, 16.8±0.6 vs. 14.3±0.5; daytime systolic ARV, 21.8±0.8 vs. 16.8±0.6; and daytime diastolic ARV, 16.2±0.6 vs. 13.4±0.5 (p<0.001 for all comparisons). CONCLUSION: From the registry data, we found that subjects with WCH or masked hypertension had higher BPV than NT. However, long-term follow-up data assessing the clinical influences of WCH on stroke are needed.

Abdominal Wall Hematoma as a Rare Complication following Percutaneous Coronary Intervention

Abdominal wall hematoma is a rare but potentially serious vascular complication that may develop after coronary angiographic procedures. In particular, an oblique muscle hematoma caused by an injury of the circumflex iliac artery is very rare, yet can be managed by conservative treatment including hydration and transfusion. However, when active bleeding continues, angiographic embolization or surgery might be needed. In this study, we report an uncommon case of injury to the circumflex iliac artery by an inappropriate introduction of the hydrophilic guidewire during the performance of a percutaneous coronary intervention.

Prevalence of Atrial Fibrillation and Relation to Echocardiographic Parameters in a Healthy Asymptomatic Rural Korean Population

Atrial fibrillation (AF) is the most common arrhythmia worldwide and a potent independent risk factor for stroke. This study aimed to determine the prevalence of AF in a population-based sample of adults in a rural region of Korea. Between January 2005 and December 2009, 4,067 individuals (60.2 +/- 11.2 yr old, M: F = 1,582:2,485) over 21 who were residents of the county of Yangpyeong, Korea, participated in the study. AF was assessed on a resting 12-lead electrocardiogram (ECG) in 4,053 of the participants. Blood tests and transthoracic echocardiography (TTE) were also performed to investigate the relationship between left ventricular mass and AF in the study group. Fifty-four cases (32 men) were diagnosed as AF among the 4,053 subjects. The crude prevalence of AF was 1.3%. It was highest (2.3%) among sixty- and seventy- year olds, and higher in men than women in all age groups over 50. The prevalence in men was 2.0%, and in women 0.9%. In univariate analysis, age, male gender, body mass index, total serum cholesterol, alanine transaminase, serum creatinine, adiponectin level, and ischemic heart disease were associated with AF. Among the TTE parameters, systolic and diastolic left ventricular systolic internal dimension (LVID), and LV ejection fraction were associated with AF. In this relatively healthy population in a rural area of Korea, the prevalence of AF is 1.3%, and increases with age. Of the TTE parameters, systolic and diastolic LVID and left atrial diameter are related to prevalence of AF.

Sick Sinus Syndrome Following Severe Hyponatremia Associated with Desmopressin Therapy / 대한내과학회지

Desmopressin diacetate arginine vasopressin (DDAVP) is a synthetic analogue of the arginine vasopressin that is widely used in the treatment of diabetes insipidus, nocturnal enuresis, and polyuria. Although it is generally well-tolerated, DDAVP can cause hyponatremia, especially in elderly patients. There are many reports of DDAVP-induced hyponatremia, but there has been only one case report in which sinus node dysfunction was caused by severe hyponatremia. Here we report a case of sick sinus syndrome that occurred during an episode of severe hyponatremia induced by chronic use of desmopressin in a 91-year-old man who had nocturnal enuresis.

Two Cases of Treatment with Thrombolysis and an Extracorporeal Membrane Oxygenator in Patients with Pulmonary Embolism and Cardiac Arrest / 대한내과학회지

Massive pulmonary embolism (PE) is associated with poor prognosis and high mortality. Moreover, patients with massive PE who present with shock have mortality rates ranging from 30% to 50%. Thrombolysis should be administered to patients with massive PE unless there are absolute contraindications to its use. However, treatment failure still occurs, and there is no consensus for the management of massive PE with cardiopulmonary arrest with regard to thrombolysis. In this study, two cases of massive PE with cardiopulmonary arrest are described, both of which were successfully treated with thrombolysis and hemodynamic support, which was administered by extracorporeal membrane oxygenation (ECMO). This report suggests that ECMO may provide safe and adequate cardiopulmonary support in patients with massive PE with refractory thrombolysis and cardiopulmonary arrest.

Association between Central Obesity and Circadian Parameters of Blood Pressure from the Korean Ambulatory Blood Pressure Monitoring Registry: Kor-ABP Registry

Central obesity has been reported as a risk for atherosclerosis and metabolic syndrome. The influence of central obesity on diurnal blood pressure (BP) has not been established. In this study, we investigated the influence of central obesity on the circadian parameters of BP by 24 hr ambulatory BP monitoring. Total 1,290 subjects were enrolled from the Korean Ambulatory BP registry. Central obesity was defined as having a waist circumference> or =90 cm in males and > or =85 cm in females. The central-obese group had higher daytime systolic BP (SBP), nighttime SBP and diastolic BP (DBP) than the non-obese group (all, P or =65 yr) also showed a higher BP MD than within the younger group (daytime SBP MD 8.23 vs 3.87, daytime DBP 4.10 vs 1.59). In conclusion, central obesity has no influence on nocturnal dipping patterns. However, higher SBP and wider PP are associated with central obesity, which is accentuated in women.

Correlation between Proximal Abdominal Aortic Stiffness Measured by Ultrasound and Brachial-Ankle Pulse Wave Velocity

BACKGROUND AND OBJECTIVES: The proximal portion of the abdominal aorta (AA) is characterized by minimal arteriosclerosis compared with other aortic segments. To assess the clinical usefulness of this characteristic, the correlation between ultrasonographically measured proximal AA stiffness and brachial-ankle pulse wave velocity (baPWV) was examined. SUBJECTS AND METHODS: 285 subjects were analyzed, half with hypertension and half with normal blood pressure. Proximal AA was examined using ultrasonography; strain, distensibility, elastic modulus, and the stiffness index were determined. After adjustment for age, gender, body mass index (BMI), systolic blood pressure (SBP), and heart rate, the relationships between baPWV and all these parameters were tested. RESULTS: The mean age of the study subjects was 58.1+/-12.8 years and the mean BMI was 24.3+/-3.8 kg/cm2. 58.9% of the subjects were female. 42.8% were hypertensive subjects. Among the hypertensive subjects, 56.0% were taking antihypertensive medication. Adjusted partial correlation coefficients for the relationship between baPWV with strain, distensibility, elastic modulus, and the stiffness index of the proximal AA were -0.203 (p=0.01), -0.121 (p=0.129), 0.304 (p=0.0001), and 0.299 (p=0.0001), respectively, in normotensive subjects. In the multivariate analyses, such correlations were observed mainly in the normotensive group, whereas there was no association among hypertensive subjects regardless of antihypertensive medication status. CONCLUSION: baPWV is moderately correlated with the stiffness parameters for the proximal AA, mainly in normotensive subjects.

A Case of Deep Vein Thrombosis after Coronary Angiography in a Patient Using Antidepressants and Anxiolytics

Deep vein thrombosis (DVT) is a rare but potentially serious complication of coronary angiography (CAG) affecting just under 5 in 10000 patients. Most of the cases regarding DVT after CAG reported in the literature were associated with procedure-related vascular complications or with risk factors for venous thromboembolism (VTE). Here, we describe the case of a 50-year-old woman during treatment for anxiety disorder, who developed significant DVT after CAG without a history of VTE and with no significant risk factors for VTE, which was treated with an anticoagulant. This case reminds us that clinicians should consider the possible occurrence of VTE after diagnostic CAG even in patients without significant risk factors.

A Case of Deep Vein Thrombosis after Coronary Angiography in a Patient Using Antidepressants and Anxiolytics

Deep vein thrombosis (DVT) is a rare but potentially serious complication of coronary angiography (CAG) affecting just under 5 in 10000 patients. Most of the cases regarding DVT after CAG reported in the literature were associated with procedure-related vascular complications or with risk factors for venous thromboembolism (VTE). Here, we describe the case of a 50-year-old woman during treatment for anxiety disorder, who developed significant DVT after CAG without a history of VTE and with no significant risk factors for VTE, which was treated with an anticoagulant. This case reminds us that clinicians should consider the possible occurrence of VTE after diagnostic CAG even in patients without significant risk factors.

A Comparison of Cornell and Sokolow-Lyon Electrocardiographic Criteria for Left Ventricular Hypertrophy in Korean Patients

BACKGROUND AND OBJECTIVES: Electrocardiography (ECG) is a cost-effective and useful method for diagnosing left ventricular hypertrophy (LVH) in a large-scale study or in clinical practice. Among ECG criteria, the Cornell product (Cor P) and Sokolow-Lyon criteria were adopted by the European Society of Hypertension-European Society of Cardiology Guidelines but have different performances among races. The aim of this study was to compare the diagnostic performance of two voltage criteria in Korean patients. SUBJECTS AND METHODS: Electrocardiography and echocardiographic LV mass of 332 (159 male, 173 female) consecutive patients were analyzed. Cornell voltage criteria and the Cor P were compared with Sokolow-Lyon voltage (Sok V) and the Sokolow-Lyon product (Sok P). The sensitivities and specificities were estimated using a receiver-operating characteristics (ROC) curve in relation to the LVH diagnosis. The sensitivities and revised cut-off values were derived at specificity levels of 90, 95, and 100%. RESULTS: The Cornell-based criteria generally showed better performance than that of the Sok V criteria and Sok P in the area under the ROC curve analysis. The revised cut-off values for the Cornell voltage criteria (20 and 16 mm for males and females, respectively) showed an improved sensitivity (19.7 and 30.3% for males and females, respectively), with a high specificity of 95%. CONCLUSION: The Cornell-based criteria had better performance than that of the Sokolow-Lyon criteria in both Korean men and women. However, revised cut-off values are needed to improve accuracy.

Unilateral Pulmonary Edema: A Rare Initial Presentation of Cardiogenic Shock due to Acute Myocardial Infarction

Cardiogenic unilateral pulmonary edema (UPE) is a rare clinical entity that is often misdiagnosed at first. Most cases of cardiogenic UPE occur in the right upper lobe and are caused by severe mitral regurgitation (MR). We present an unusual case of right-sided UPE in a patient with cardiogenic shock due to acute myocardial infarction (AMI) without severe MR. The patient was successfully treated by percutaneous coronary intervention and medical therapy for heart failure. Follow-up chest Radiography showed complete resolution of the UPE. This case reminds us that AMI can present as UPE even in patients without severe MR or any preexisting pulmonary disease affecting the vasculature or parenchyma of the lung.

The Relationship Between Ambulatory Arterial Stiffness Index and Blood Pressure Variability in Hypertensive Patients

BACKGROUND AND OBJECTIVES: Ambulatory arterial stiffness index (AASI) is well known as a predictor of cardiovascular mortality in hypertensive patients. Mathematically, AASI reflect the standard deviation (SD) of blood pressure (BP) variation. AASI is measured higher levels in non-dipper than dipper. Thus, AASI has a possibility of not only reflecting arterial stiffness but also BP variability and/or autonomic nervous dysfunction. SUBJECTS AND METHODS: Consecutive data from 418 untreated hypertensive patients were analyzed retrospectively. We examined the association between the 24-hour ambulatory BP monitoring (ABPM) parameters and AASI. RESULTS: AASI had a simple correlation with age (R=0.189, p<0.001), relative wall thickness (RWT) (R=0.115, p=0.019), left ventricular mass index (LVMI) (R=0.192, p<0.001), average systolic BP (SBP) (R=0.232, p<0.001), average pulse pressure (PP) (R=0.363, p<0.001), SD of diastolic BP (DBP) (R=-0.352, p<0.001), SD of PP (R=0.330, p<0.001), SD of heart rate (HR) (R=-0.268, p<0.001), and nocturnal dipping (R=-0.137, p=0.005). In multiple linear regression analysis model including clinical parameters and 24 hour-ABPM parameters, independent predictors of AASI were SD of PP (beta=1.246, p<0.001), SD of DBP (beta=-1.067, p<0.001), SD of SBP (beta=-0.197, p<0.001), and non-dipper (beta=0.054, p=0.033). CONCLUSION: AASI is closely correlated with BP variability. The result of this study shows that AASI is not only a parameter for arterial stiffness, but also a parameter for BP variability.

Non-Dipper Pattern is a Determinant of the Inappropriateness of Left Ventricular Mass in Essential Hypertensive Patients

BACKGROUND AND OBJECTIVES: Inappropriately high left ventricular mass (iLVM) is known to be related to cardiovascular prognosis. A non-dipper pattern has a greater mean left ventricular (LV) mass than the dipper pattern in hypertensive patients. However, the appropriateness of LV mass in dipper or non-dipper patterns has not been adequately investigated. The aim of this study was to define the relationship between nocturnal dipping and the appropriateness of LV mass. SUBJECTS AND METHODS: Using the ambulatory blood pressure monitoring (ABPM) database, the data of 361 patients who underwent ABPM and echocardiography was analyzed retrospectively. Appropriateness of LV mass was calculated as observed/predicted ratio of LV mass (OPR) using a Korean-specified equation. Nocturnal dipping was expressed as percent fall in systolic blood pressure (BP) during the night compared to the day. RESULTS: Daytime, nighttime and 24 hours BP in hypertensive patients was 140.4+/-14.8 mmHg, 143.7+/-15.2 mmHg and 129.4+/-20.0 mmHg, respectively. OPR was 106.3+/-19.9% and nocturnal dipping was 10.2+/-10.9 mmHg. In a multiple linear regression model, 24 hours systolic BP (beta=0.097, p=0.043) and nocturnal dipping (beta=-0.098, p=0.046) were independent determinants of OPR as well as age (beta=0.130, p=0.025) and body mass index (BMI) (beta=0.363, p25 kg/m2). CONCLUSION: The non-dipper pattern is independently associated with iLVM in hypertensive patients as well as obesity.

Clinical Implications of Ambulatory and Home Blood Pressure Monitoring

Because blood pressure (BP) is an ever changing hemodynamic phenomenon, a BP value, once measured at a physician's office (Office BP), is often unrepresentative of an individual's true BP status. Both ambulatory blood pressure monitoring (ABPM) and home blood pressure monitoring (HBPM) provide more accurate and reproducible estimate of BP, and produce stronger predictive ability for cardiovascular outcome than conventional office BP. Two BP measuring techniques, ABPM and HBPM have been widely in clinical use for the detection and management of hypertension. However, they have different advantages and limitations in practice. At present, it has become crucial to understand the characteristics and clinical implications of these BP measuring techniques for those responsible for the care of hypertensive patients.

Beneficial Effect of Efonidipine, an L- and T-Type Dual Calcium Channel Blocker, on Heart Rate and Blood Pressure in Patients With Mild-to-Moderate Essential Hypertension

BACKGROUND AND OBJECTIVES: Efonidipine hydrochloride, an L- and T-type dual calcium channel blocker, is suggested to have a heart rate (HR)-slowing action in addition to a blood pressure (BP)-lowering effect. The aim of this study was to determine the effect of efonidipine on HR and BP in patients with mild-to-moderate hypertension. SUBJECTS AND METHODS: In a multi-center, prospective, open-labeled, single-armed study, we enrolled 53 patients who had mild-to-moderate hypertension {sitting diastolic BP (SiDBP) 90-110 mmHg}. After a 2-week washout, eligible patients were treated with efonidipine (40 mg once daily for 12 weeks). The primary end point was the change in HR from baseline to week 12. The secondary end-point included the change in trough sitting BP and 24-hour mean BP between baseline and week 12. Laboratory and clinical adverse events were monitored at each study visit (4, 8, and 12 weeks). RESULTS: Fifty-two patients were included in the intention-to-treat analysis. After 12 weeks of treatment with efonidipine, the resting HR decreased significantly from baseline to week 12 {from 81.5+/-5.3 to 71.8+/-9.9 beats/minute (difference, -9.9+/-9.0 beats/minute), p<0.0001}. The trough BP {sitting systolic blood pressure (SiSBP) and SiDBP} and 24-hour mean BP also decreased significantly (SiSBP: from 144.6+/-8.2 to 132.9+/-13.5 mmHg, p<0.0001; SiDBP: from 96.9+/-5.4 to 88.3+/-8.6 mmHg, p<0.0001, 24-hour mean systolic BP: from 140.4+/-13.5 to 133.8+/-11.6 mmHg, p<0.0001; 24-hour mean diastolic BP: from 91.7+/-8.7 to 87.5+/-9.5 mmHg, p<0.0001). CONCLUSION: Efonidipine was effective in controlling both HR and BP in patients with mild-to-moderate hypertension.

Association Between Inappropriateness of Left Ventricular Mass and Left Ventricular Diastolic Dysfunction: A Study Using the Tissue Doppler Parameter, E/E'

BACKGROUND AND OBJECTIVES: The structural significance of the inappropriateness of left ventricular mass (iLVM) is known to be an important prognostic factor for cardiovascular events; however, the functional changes associated with iLVM have not been established. This study was performed to determine if diastolic dysfunction is associated with iLVM using a tissue Doppler technique. SUBJECTS AND METHODS: Three hundred sixty consecutive subjects, including 221 hypertension patients from the echocardiography database, were analyzed. Regarding the appropriateness of left ventricular (LV) mass, an observed/predicted ratio of LV mass (OPR) >130% was defined as inappropriate. Echocardiographic parameters, including early diastolic peak velocity (E)/late diastolic peak velocity (A), deceleration time (DT), isovolumetric relaxation time (IVRT), and E/early mitral annulus velocity (E'), were compared between the appropriate LV mass (aLVM) group and the iLVM group. RESULTS: Among transmitral flow parameters, only the E velocity was negatively correlated with the OPR when adjusted for age (adjusted r=-0.107, p=0.04). Based on multiple regression analysis, the OPR (beta=0.163, p=0.003), as well as age (beta=0.286, p=0.0001), systolic blood pressure (beta=0.120, p=0.019), fasting blood glucose (beta=0.098, p=0.042), and male gender (beta=0.157, p=0.002) were independent factors determining E/E'. The cholesterol level was not an independent factor (beta=-0.059, p=0.355). In the iLVM group (n=105), the adjusted E/E' was higher than in the aLVM group (n=255; 11.7+/-3.4 vs. 10.8+/-3.1, p=0.02), while the peak E flow velocity was significantly lower than in the aLVM group (70.9+/-15.1 vs. 75.5+/-17.6, p=0.03). CONCLUSION: Inappropriateness of LV mass is independently associated with increased E/E'. Thus, E/E' may be a useful parameter for the evaluation of diastolic dysfunction.

Clinical Factors Associated with Brachial-Ankle Pulse Wave Velocity in Patients on Maintenance Hemodialysis

Pulse wave velocity (PWV) is a main parameter for arterial stiffness. In patients with end-stage renal disease (ESRD), PWV is known to be associated with increased mortality. But factors related to the increased PWV in ESRD patients are not well defined. In addition, the carotid-femoral PWV (cfPWV) measurement, which traditionally has been used to evaluate arterial stiffness, has low reproducibility. Recently, brachial-ankle PWV (baPWV) measurement, which can be performed more easily than cfPWV measurement, has become available as a means of measuring PWV. The aim of this study is to investigate the clinical factors associated with increased baPWV in ESRD patients. BaPWV was examined for 65 ESRD patients on maintenance hemodialysis during the period between the 7th to the 11th of February in 2005 using VP-1000. The clinical factors included age, sex, smoking history, blood pressure, diabetes, body mass index, interdialytic weight gain, duration of dialysis, lipid profile, uric acid, albumin, creatinine, C-reactive protein, calcium, phosphate, intact parathyroid hormone, and hematocrit were analyzed regarding associations (or to determine associations) with baPWV. The median age was 53.8+/-12.0, 31 males and 34 females. BaPWV was 18.9+/-5.2 m/s and there was no significant difference between gender (18.1+/-4.4 m/s vs 19.4+/-5.9 m/s, p=NS). In multiple regression models, age, predialysis systolic blood pressure, and diabetes were independent variables. In conclusion, age, systolic blood pressure, and diabetes were correlated with baPWV in ESRD patients. Thus baPWV measured by simple, noninvasive methods may become available for screening high risk groups in ESRD patients, although further longitudinal studies are necessary.

Association with Left Ventricular Diastolic Function Parameters and Right Brachial-ankle Pulse Wave Velocity in Hemodialysis Patients / 대한신장학회지

PURPOSE: Arterial stiffness is a major independent risk factor for cardiovascular morbidity and mortality in hemodialysis patients. It is hypothesized that arterial stiffness factor is attributable to the structural and functional changes of left ventricle (LV) caused by increased cardiac workload. So we investigated the relationship between brachial-ankle pulse wave velocity (baPWV) and diastolic dysfunction of left ventricle using echoardiographic transmitral blood flow pattern. METHODS: For 96 subjects (48 control patients, 48 hemodialysis patients), baPWV and echocardiographic indices for diastolic function, i.e. transmitral E, A, E/A, DT, IVRT were measured just before hemodialysis session. Role of baPWV was tested in a multiple regression model including age, gender, body mass index, predialysis blood pressure, heart rate, LV mass index and interdialysis weight gain. RESULTS: In the control group, LV mass index (beta=-0.350) and rbaPWV (beta=-0.403) had an independently correlation with E/A ratio. Rt-baPWV was independently correlated with DT (beta=-0.410) and IVRT (beta=0.500). In the hemodialysis group, systolic blood pressure (beta=-0.389) and heart rate (beta=-0.403) were the factors of E/A ratio. Rt-baPWV (beta=-0.557) was the factor determining E/A ratio only in female hemodialysis patients. CONCLUSION: PWV is independently correlated with E/A ratio only in female hemodialysis patients. Their relationship is limited or weak compared to normal control group.

Significance of QT Dispersion as a Prognostic Factor in Hyperkalemia

PURPOSE: To date, it has been impossible to relate the occurrence of ventricular arrhythmia to survival in hyperkalemia. QT dispersion is thought to reflect the inhomogeneity of ventricular repolarization and to be related to ventricular-arrhythmia-induced sudden cardiac death in various medical conditions. Therefore, the purpose of this study was to investigate to use QT dispersion as a prognostic marker in hyperkalemia and to suggest treatment guidelines for hyperkalemia by analyzing the correlations between the QT dispersion on the initial ECG and the treatment outcomes. METHODS: This study's population was comprised of 104 patients with serum potassium concentrations > or =5.5 mEq/L, who were divided into 2 groups; group 1 was the survival group (n=81), group 2 was the death group (n=23). We reviewed retrospectively the underlying diseases, electrolytes, treatment outcomes and the clinical and ECG findings during the initial and the recovery states. The QT interval for each lead was measured manually on an enlarged (X1.5) ECG. The QT interval was measured from the first deflection of the QRS complex to the point of the T wave offset, and the corrected QT interval was obtained by using B a z e t t's formula. The QT dispersion and the corrected QT dispersion were defined as the differences between the minimal and the maximal QT values and between the corresponding corrected QT values for each of the 12 leads, respectively. RESULTS: The treatment outcomes were not related to the initial serum potassium and the hourly serum potassium change rates. For hyperkalemia > or =7.0 mEq/L, the death group had significantly larger QT dispersion than the survival group (death group = 95.6+/-15.4 msec, survival group = 51.8+/-17.5 msec, p or =7.0mEq/L, QT dispersion above 65 msec had a 93.8% sensitivity, a 79.4% specificity, and a 68.2% positive predictive value for death. CONCLUSION: For hyperkalemia > or =7.0 mEq/L, QT dispersion above 65 msec should be considered to be a prognostic marker for prediction of the treatment outcome.