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Ventricular tachycardia induced by tilt table testing.

We herein report the case of a 20-year-old man with a history of epilepsy who presented with frequent transient loss of consciousness (T-LOC) and polymorphic ventricular tachycardia (VT) with QT interval prolongation. Blood investigations revealed panhypopituitarism. Following a biopsy, he was diagnosed with brain germinoma. During the biopsy, he had an episode of polymorphous VT with QT prolongation. There was no recurrence of T-LOC following chemotherapy and hormone replacement therapy. This case indicates the importance of checking the QT interval in patients with T-LOC, including those with seizures and brain tumors, to ensure appropriate treatment.

Introduction: Atrial arrhythmia (AA) and left ventricular systolic dysfunction (LVSD) frequently co-exist, which loom as burgeoning public health problems. It is difficult to determine whether a tachycardia is the indicator or consequence of LVSD in patients with tachycardia and LVSD. Tachycardia mediated cardiomyopathy (TCM) raises a “chicken or egg” question. Regardless of the etiology, the patients with severe LVSD are considered as the candidate for the implantation of cardioverter defibrillator as primary prevention. It is well known that the LVSD improves after the successful treatment of AA in TCM population. However, enlarged left ventricular end-diastolic dimension (LVDd) is considered as a parameter of irreversible LVSD. Hypothesis: Enlarged LVDd could not be a predictor for irreversible LVSD in patients with AA. Methods: We assessed patients with persistent AA and heart failure (Ejection Fraction (EF) Results: Twenty-five patients with persistent AA and LVSD (23 men; mean age 63.8±9.3 years) were enrolled in this study. After restored and maintained SR, EF and left ventricular end-systolic volume (ESV) and BNP were improved in all patients respectively (EF 30.7±10.7 to 54.0±7.3%, ESV; 82.1±32.4 to 50.6±24.1ml, BNP; 379.2±237.9 to 48.0±29.7pg/ml P60mm were observed in 5 patients (25%) before the treatment. EF was normalized in patients with severe LVSD (EF Conclusions: The unnecessary device implantation could be avoided in patients with AA and severe LVSD with aggressive rhythm control therapy. Even in the patients with severe LVSD and enlarged LVDd, LVSD is reversible when AA exists.

BACKGROUND An adaptive cardiac resynchronization therapy (aCRT) algorithm has been described for synchronized left ventricular (LV) pacing and continuous optimization of cardiac resynchronization therapy (CRT). However, there are few algorithmic data on the effect of changes during exercise.Methods and Results:We enrolled 27 patients with availability of the aCRT algorithm. Eligible patients were manually programmed to optimal atrioventricular (AV) and interventricular (VV) delays by using echocardiograms at rest or during 2 stages of supine bicycle exercise. We compared the maximum cardiac output between manual echo-optimization and aCRT-on during each phase. After initiating exercise, the optimal AV delay progressively shortened (P

Background Computed tomography is the best noninvasive imaging modality for evaluating valve leaflet calcification. Objective To evaluate the association of aortic valve leaflet calcification with instantaneous valve opening and closing using dynamic multidetector computed tomography (MDCT). Methods We retrospectively evaluated 58 consecutive patients who underwent dynamic MDCT imaging. Aortic valve calcification (AVC) was quantified using the Agatston method. The aortic valve area (AVA) tracking curves were derived by planimetry during the cardiac cycle using all 20 phases (5% reconstruction). da/dt in cm 2 /s was calculated as the rate of change of AVA during opening (positive) or closing (negative). Patients were divided into 3 three groups according to Agatston score quartile: no AVC (Q2, Score 0, n = 18), mild AVC (Q3, Score 1–2254, n = 24), and severe AVC (Q4 Score >2254, n = 14). Results In multivariable linear regression, compared to the non AVC group, the mild and severe AVC groups had lower maximum AVA (by −1.71 cm 2 and −2.25 cm 2 , respectively), lower peak positive da/dt (by −21.88 cm 2 /s and −26.65 cm 2 /s, respectively), and higher peak negative da/dt (by 13.78 cm 2 /s and 18.11 cm 2 /s, respectively) (p Conclusions AVA and its opening and closing were influenced by leaflet calcification. The present study demonstrates the ability of dynamic MDCT imaging to assess quantitative aortic valve motion in a clinical setting.

We report an autopsy-proven case of a 33-year-old man who died of intimal sarcoma of the pulmonary artery. A large mass (5×4 cm) occluded the main and bilateral pulmonary arteries. Tumor cell morphology was consistent with that of undifferentiated pleomorphic sarcoma. Comprehensive histological observation of 18 pulmonary arteries from proximal to distal revealed continuous extension of the tumor from the main to the subsegmental arteries along the intima, forming an arteriosclerosis-like intimal thickening. Distal small arteries were also affected by eccentric intimal thickening or recanalization. Lung parenchyma was not involved, although there were two wedge-shaped small pulmonary infarctions caused by tumorous obstruction of the associated arteries. Histological results indicated that the intimal sarcoma in the pulmonary artery, which appeared occlusive with growth limited to the proximal artery, had in fact already spread more peripherally than expected. Both the proximal lesions and the distal small arteries were affected by peripheral tumor emboli or by pulmonary hypertension induced by the proximal tumor. However, as seen in this case, most of the occlusive tumor was located locally and intraluminally, in the proximal artery, and removing the proximal tumor by pulmonary endarterectomy was considered effective for symptomatic improvement.

Long-Term Observation with ILR. Introduction: In the literature, the average diagnostic yield of the implantable loop recorder (ILR) is reported to be 35% over an observation period generally less than 18 months. The aim of this study was to evaluate the diagnostic value of ILR during very prolonged observation. Methods and Results: Consecutive patients who had received one or more (in the case of battery exhaustion before diagnosis) ILR (Reveal/plus/DX, Medtronic Inc.) from 2001 to 2010 were included. The diagnostic ECG was classified according to the ISSUE classification. We analyzed 157 patients (87 males, 69 ± 14 years): 70 of these were followed up for ≥18 months. The estimated cumulative diagnostic rates were 30%, 43%, 52%, and 80% at 1, 2, 3, and 4 years, respectively; 26% of diagnoses were made after 18 months. The diagnostic yield was independent of structural heart disease, bundle branch block, number of syncopes, age, and gender; the median time to diagnosis of ISSUE type 1 patients was shorter than that of the others (4 [2;10] vs. 16 [6;23] months; P = 0.003). During the observation period, 3 patients (1.9%) died and none suffered arrhythmic death. Conclusions: Prolonging observation up to 4 years increased the diagnostic value of ILR in syncopal patients and was safe. A quarter of patients diagnosed needed more than 18 months of follow-up. As consequence, when a strategy of prolonging monitoring is chosen, monitoring should be maintained even for several years until diagnosis is established. (J Cardiovasc Electrophysiol, Vol. 23, pp. 67-71, January 2012)

Recently, the remote transmission of data detected by implantable loop recorders (ILRs) has become available. The aim of this study was to evaluate effectiveness and acceptance of remote monitoring in the clinical management of syncope and palpitations in patients with ILR. Methods and results Consecutive patients implanted with ILR (Reveal DX/XT Medtronic, Inc.) and followed up by means of remote moni- toring (CareLink w ) were included. The patients were requested to transmit the data stored in the ILR every week, via the CareLink system, or more frequently during the first period. Patient acceptance of ILR was evaluated by means of a questionnaire concerning physical and mental components. Forty-seven patients (27 males, average age 64+ 19 years) were enrolled and followed up for 20+ 13 weeks. Thirty-two patients (68%) had at least one ECG recording of a true relevant event. The mean time from ILR implantation to the first true relevant ECG was 28+ 49 days, which was 71+ 17 days less than in the clinical practice of 3-monthly in-office follow-up examinations. Thirty- eight patients (81%) had at least one false arrhythmic event, mainly false asystole and false fast ventricular tachycardia. In the absence of Carelink transmission, at least one episode of memory saturation of ILR would have occurred in 21 patients (45%) that would have limited the diagnostic yield. Patient compliance was good even though one- fifth had some minor psychological concern regarding the ILR implant. CareLink was well accepted and judged easy to use. Conclusion Remote monitoring enhances the diagnostic effectiveness of Reveal, limiting the risk of memory saturation due to the high number of false detections and reducing the time to diagnosis. Both ILR and CareLink were well accepted and well tolerated by the patients, as they were considered useful.

Distinctive Electrogram and Aortography of Coronary Cusp. Background: The coronary cusps have recently become target sites for radiofrequency catheter ablation of both outflow tract ventricular arrhythmias originating near the coronary cusps (CC-VA) and atrial tachyarrhythmias such as focal atrial tachycardia originating near the noncoronary cusp (NCC-AT). However, the relation between local electrograms recorded at each CC during sinus rhythm and their anatomical position as assessed by aortography has not yet been systematically described. Methods and Results: In 28 patients undergoing RFCA for CC-VA or NCC-AT, amplitudes of the atrial and ventricular potentials at the CCs were measured during sinus rhythm, and the atrial/ventricular (A/V) potential ratio was computed. Relative positions of the CCs were assessed by aortography in 2 X-ray projections. In the right (RCC) and left coronary cusps (LCC), amplitudes of the ventricular potential were larger than those of the atrial potential, leading to an A/V ratio

For the purpose of discriminating between cases of nephrotic syndrome with and without corticosteroid effect, a linear discriminant function was applied in attempt to predict the effect of corticosteroid by the use of a computer. The parameters used were 15-min values of the PSP test, urinary protein, serum cholesterol, renal biospy findings, the number of red cells in the urinary sediment and immunoglobulin clearance ratio. The rate of correct prediction using the function with immunoglobulin clearance ratio was 87.0 %.

A multivariate analysis of CAMPAS-PX2 can increase its diagnostic accuracy in differential diagnosis of pancreatic cancer from benign pancreatic or extrapancreatic disease, when compared with CA19-9 alone. However, the improvement in diagnostic accuracy is still not satisfactory in spite of an elaborate combination of serum markers in diagnosis for pancreatic cancer. Optimal combination of a sensitive serum marker and another diagnostic modality, such as ultrasonography, can be a practical way to improve important diagnostic and cost-effectiveness in diagnosis for pancreatic cancer.No specific biological test has yet been developed for diagnosis of pancreatic cancer, although increasing numbers of tumor markers become available. For improvement in the diagnostic and cost effectiveness, it is important to select optimal combination of several serum markers relatively independent of each other.A new model of discriminant function, computer-aided multivariate and pattern analysis system for pancreatic cancer examination 2 (CAMPAS-PX2), was developed based on the data of the 23 serum tumor markers from the first prospective trial (1) to differentiate between pancreatic cancer and benign pancreatobiliary disease by logistic regression analysis using a stepwise selection method. In 243 patients suspected of having pancreatic pancreatic cancer by a multicenter prospective study, the diagnostic value of the multivariate analysis, CAMPAS-PX2, was compared with the 23 markers.Pancreatic cancer was subsequently identified in 27 patients. Positive in disease, negative in health, and area under receiver operating characteristic curve were significantly higher by CAMPAS-PX2 (89, 87, 91%) than by CA 19-9 (78, 82, 84%), the most sensitive marker among the 23 markers.

Background: The role of autonomic effects in the occurrence and maintenance of atrial fibrillation (AF) has undergone little investigation in the remodeling heart. Methods and Results: In the present study, 2 groups were studied: those with complete atrioventricular block (AVB) produced by radiofrequency current application (AVB dogs, n=17) and those not undergoing AVB (sham dogs, n=5). Eight weeks after creation of AVB, electrophysiologic study, including pulmonary vein (PV) pacing for AF induction, was performed under vagal nerve stimulation (VNS) and sympathetic stimulation (SS) in both groups. After 8 weeks, atrial dimensions and the percentage of fibrosis in the atria were significantly greater in the AVB dogs. In AVB dogs, atrial and PV effective refractory periods were shorter (P

Aims The purpose of this retrospective study was to assess characteristics of patients who had suffered atrial flutter (AFL) with 1:1 atrioventricular (AV) conduction (1:1 AFL). Methods and results Subjects were 8 patients (61 ± 14 years) with documented 1:1 AFL, and 101 AFL patients without a history of 1:1 AFL (control patients). 1:1 AFL occurred during physical activity with a ventricular rate of 218 ± 18 bpm. Antiarrhythmic agents were administered to all eight 1:1 AFL patients, whereas AV nodal conduction-suppressing agents were administered to four. The maximum ventricular rate at which 1:1 AV conduction occurred was significantly lower than when spontaneous 1:1 AFL occurred (164 vs. 218 bpm, P < 0.05). The 1:1 AFL patients had a significantly longer AFL cycle length (CL) (292 vs. 258 ms, P < 0.05) and more rapid AV nodal conduction time (maximum 1:1 AV conduction: 375 vs. 464 ms, P < 0.05) than did control. Arrhythmia had occurred in patients with an AFL CL ≥ 250 ms and a CL of maximum 1:1 AV conduction ≤400 ms. Conclusion Clinicians should be aware of the potential for 1:1 AV conduction in AFL patients, especially in those with remarkable prolongation of the CL in addition to enhanced AV conduction.

Introduction: The role of the autonomic nervous system in inducing pulmonary vein (PV)-triggered atrial fibrillation (AF) and the termination mechanism of the AF are unknown. The purpose of this study was to elucidate the mechanism of the conversion of a tachycardia within a PV into AF under autonomic stimulation and the termination mechanism of the AF in normal canine hearts. Methods and Results: In open-chest dogs, the electrophysiologic parameters were measured under vagal stimulation (VS) or an isoproterenol administration. The effects of the VS or isoproterenol on the PV tachycardias (PVTs), which were created by burst pacing from a PV or the application of aconitine onto the PV, were evaluated. Pilsicainide, a Na channel blocker, was administered during the induced AF. VS and isoproterenol shortened the atrial and PV effective refractory periods. In the pacing model, the VS converted the PV rapid activations into sustained AF in 9 of 12 dogs during pacing cycle lengths ≤120 msec, but the isoproterenol did not cause any sustained AF. In the aconitine model, the VS increased the rate of the aconitine-induced PVTs and transformed them into sustained AF in all 14 dogs, whereas the isoproterenol did not induce AF, and decreased the PVT rate. In all 14 dogs the sustained AF was terminated by pilsicainide, which had suppressive effects on the PVT as well as atria and PV-atrial junction. Conclusions: These findings indicate that the vagal effects affecting the PVT and atria facilitate the onset and maintenance of PV-triggered AF in normal canine hearts.

Evaluation methods for arteriosclerosis have been established, but most of them are invasive. In recent years, noninvasive diagnosis for arteriosclerosis can be achieved by high resolution echography. However, even this new diagnostic method cannot diagnose until the beginning of the morphologic changes of the arteries by stenosis. There is little value achieved if the arteriosclerosis is detected after the stenosis of the arteries has progressed. Also, we thought that a noninvasive method for evaluating the arteriosclerosis should be used. We introduced a idea of rheological dynamics into analysis. For example the cross-section area of a young elastic artery may expand quickly and become wide, whereas an old one is narrow and slowly expands due to blood pressure. We call this functional tissue characterization, and investigated the common carotid artery of about 160 persons. In this way we diagnosed age-related arteriosclerosis quantitatively by investigating parameters of the nonlinear pressure and area of the common carotid artery curve. Furthermore, we were able to separate a hypertension group and a physically normal group quantitatively as a result of having evaluated the arteriosclerosis due to various vascular diseases.

Introduction: The average diagnostic yield of the implantable loop recorder (ILR) is reported to be 35% over an observation period generally less than 18 months. The aim of this study was to evaluate the diagnostic value of ILR during prolonged observation. Methods and Results: Consecutive patients who had received one or more ILR (Reveal/plus/DX, Medtronic, Inc.) were included. The diagnostic ECG was classified according to the ISSUE classification. We analyzed 159 patients (88 males, 70±14 years): 70 of these were followed up for >18 months. The cumulative diagnostic rates were 30%, 43%, 52% and 80% at 1, 2, 3 and 4 years, respectively. The diagnostic yield was independent of structural heart disease, bundle branch block, number of syncopes, age and gender; the median time to diagnosis of ISSUE type 1 patients was shorter than that of the others (4 [2;10] v.s. 16 [6;23] months; p=0.003). During the observation period, 3 patients (1.9%) died and none suffered arrhythmic death. Conclusions: Prolonging observation increased the diagnostic value of ILR in syncopal patients and was safe. As consequence, when a strategy of prolonging monitoring is chosen, monitoring should be maintained even for several years until diagnosis is established.

We have studied 8 normal subjects, and 12 patients with idiopathic thrombocytopenic purpura whose platelet counts ranged from 9 x 10(9)/L to 40 x 10(9)/L. Autologous platelets labeled with 111Intropolone were used for evaluation of mean platelet survival, platelet turnover, platelet sequestration sites, and platelet production (turnover) to clearance (sum of platelet uptake in the liver and the spleen) ratio. Platelet survival correlated directly with platelet counts. There was no significant correlation between the platelet sequestration pattern and platelet count, survival, or turnover. Sum of platelet uptake in the liver and the spleen showed a significant inverse correlation with platelet survival. No significant correlation was found between platelet turnover and platelet count. There was a significant correlation between the platelet production to clearance index when all subjects were analyzed. The distribution of platelet turnover showed considerable individual variation; eight of twelve patients showed platelet turnover less than mean minus 2SD of the control value, but others showed normal range. We conclude that although platelet destruction mechanism in RES shows a primary role of thrombocytopenia, impaired rate of effective thrombopoiesis may also contribute to disease severity in ITP.

The primary purpose of clinical decision-making is to determine the most adequate treatment for individual pathological conditions, and the process of diagnosis and treatment constitutes a feedback loop. The present study was undertaken to apply “optimal control theory” to this process of clinical decision-making. The basic requirements for the application of optimal control theory in the clinical setting is presented and a clinical application, “adaptive control program,” is proposed for the control of blood glucose level in diabetic coma using a simulation model of blood glucose kinetics.

A mathematical model of the cardiac conduction system has been developed. The mechanisms of cardiac arrhythmias are described mathematically, and the heart is modeled as a network, where each element is defined by a unique set of time parameters from the action potential. The mathematical description is separated from the network structure, thus making it possible to run the model with different network sizes. Simulated ECG curves are produced in each case. This model is especially suited for rhythm studies, and a variety of different cardiac arrhythmia mechanisms has been simulated such as reentry, reflection, modulated parasystole, and different kinds of block.

The survival time analysis of adult patients with nephrotic syndrome was done by Weibull distribution function and exponential-Weibull model. The results were, 1)the period from onset to death of the disease followed a Weibull distribution function with an increasing failure rate, 2)the expectation of survival time by exponential-Weibull model showed a sufficient adequancy of this model for use, 3)the risk analysis using exponential-Weibull model indicated that erythrocyte sedimentation, systolic blood pressure, blood uria nitrogen, red blood cells in urinary sediment and pathological classification of renal biopsy were the main risk factors to death.

The purpose of clinical diagnosis is to determine the most fitting treatment for individual pathological conditions, and the process of diagnosis and treatment is one of feedback control system. In this paper, application of “optimal control theory” to diagnostic process was discussed and one example of computer program was showed. When diagnostic process is regarded as one of control system, medical treatment, pathological internal conditions and clinical findings are replaced to input variables, state variables and output variables respectively, and if the interrelationship of these three variables is quantitatively represented, it becomes to a problem of optimal control theory. As a clinical application, “insulin therapy in diabetic coma” was proposed. Injection of insulin and infusion therapy as input variables, and blood glucose level and insulin level state variables were used respectively, and the iterrelationship was mathematically represented based on the simulation study of blood glucose kinetics. This model was programmed for digital computer. When observed data of blood glucose level and details treatment were entered, the dosis of insulin to be injected now, fitting to the desired blood glucose level after adequate time, is computed.

The prognoses of adult patients with nephrotic syndrome were analyzed by two types of Markov model. One is the 3 state Markov model which consists of complete remission, incomplete remission and death states and the other one is the 4 state one in which the complete remission state in the 3 state model is devided into 2 states, never-relapse state and one having a possibility of relapse. The results were as follows; 1)the 3 state model estimated extremely poor or somewhat different prognosis comparing with the observed one. 2)The estimated prognosis by the 4 state model showed a good agreement with the actual one and the clinical empirical knowledge. Furthermore, the transition matrix of this model had acceptable stability. These suggested the validity of the prognostic estimation of adult nephrotic syndrome by the 4 state Markov model.

"Circular deviation ", the particular fluctuation of urea clearance following abrupt change of urine flow was observed in normal adults. This phenomenon was ascertained also in patients with diabetes insipidus by the administration of pitressin. The circular deviation in patients with renal, diseases showed an atypical pattern. These resuls were discussed from the viewpoint of countercurrent hypothesis.

Background: Of the syncope types, arrhythmic syncope is the most life threatening and therefore requires proper treatment. However, the clinical predictors of arrhythmic syncope remain unknown. Some patients with syncope suffer from head injury, a serious side effect whose importance in the differential diagnosis of syncope has not been fully studied. Here, we attempted to identify the clinical characteristics of arrhythmic syncope, including the role played by head injuries. Methods: We studied inpatients referred to the cardiology section for the diagnosis and treatment of syncope. Clinical characteristics including age, sex, incidence of head injury during syncope, and cardiologic studies were evaluated in patients with arrhythmic and non-arrhythmic syncope. Results: Of 5590 inpatients, 273 (4.8%) (170 men; mean age, 61±17 years) suffered a syncopal episode before admission, 119 (43%) of whom were diagnosed with arrhythmic syncope and 30 (11%) of whom were undiagnosed. In multivariate analysis, age >65 years (65% vs. 42%, p

A new system has been developed in which the human body surface potentials are displayed in a 3-dimensional format using computer graphics. A wire-frame model of the human torso is constructed using geometrical data from several cross-sectional slices. The body surface potentials are measured and the isopotential lines drawn. By mapping the co-ordinates obtained with the isopotential line subroutine to the X, Y and Z torso arrays, a 3-dimensional representation of the depolarization wave travelling across the body surface can be displayed. The deviations from its normal path are clearly seen in the 2 clinical cardiac conditions presented (right bundle branch block and left ventricular premature beat). The increased realism and spatial resolution, as compared to ECG and the 2-dimensional contour map, lead to a clear understanding and interpretation of the underlying electrical phenomena of the heart while making a diagnosis or presenting experimental results.

Several aspects of renal dysfunction was analysed biomathematically and the following results were obtained : (1) A mathematical analysis of diuretic response was developed to show a new diagnostic method for differentiating the causative factors involving in edema formation. The diuretic response test may be beneficial in dertermining the indication of antialdosterone agents in the treatment of the patients with edema. (2) A quantitative index of potassium excreting potency of the diuretic was introduced. (3) The mechanism of the delayed excretion of cations in the aged after administration of sodium thiosulfate was discussed. (4) Mathematical studies of the PSP excretion test revealed that the mode of excretion of PSP followed an exponential function. (5) The ideal excretion curves of PSP with urinary dead space is given and cases showing an abnormal curve were illustrated. (6) The mechanism of the discrepancy of PSP test and PAH clearance in the patients with heart failure was discussed. (7) Mathematical analysis of the mechanism of urea excretion in patients with renal failure revealed that there may be certain kinds of metabolic regulation and a decrease of the rate of urea production (the rate of protein metabolism) when renal function decreases.

1) It has been revealed that glycine, threonine, and histidine have their own Tm. Experimentally an analysis is made of the titration curve of the aminoacids after loading of amino-acid-mixture and 1-histidine loading to patients with renal diseases and to normal subjects. A reabsorption ratio is decreased in renal disease cases in a range up to the load area of Tm. 2) An increase of loaded amounts of amino-acids resulted in a gentle continuous slope but never "shoulder" on the titration curve. This "shoulder" phenomenon observed on the glucose titration curve is considered to be due to the presence of the nephron population. It is therefore, not referable to aminoacids. Assuming that the transfer reaction proceeds as follows : A+B AB

1) Urinary urea/nonurea ratio is closely related to urinary concentrating ability and indices indicating renal water economy in patients with renal diseases. 2) Two different responses between urinary concentrating ability or renal water economy to urinary urea/nonurea ratio in patients with chronic glomerulonephritis and chronic pyelonephritis were observed. 3) Urea plays the role on urinary concentration and renal water economy under an optimal co-existence of nonurea solute. Urea itself was not effective enough to save water. 4) Clinical availability of the use of indices indicating renal water economy was demonstrated. 5) Urea transport in the renal medulla could not be explained by a passive diffusion.