Clinical Structural Anatomy of the Inferior Pyramidal Space Reconstructed Within the Cardiac Contour Using Multidetector‐Row Computed Tomography

Although many studies have described the detailed anatomy of the inferior pyramidal space, it may not be easy for cardiologists who have few chances to study cadaveric hearts to understand the correct morphology of the structure. The inferior pyramidal space is the part of extracardiac fibro‐adipose tissue wedging between the 4 cardiac chambers from the diaphragmatic surface of the heart. Many cardiologists have interests in pericardial adipose tissue, but the inferior pyramidal space seems to have been neglected. A number of important structures, including the coronary sinus, atrioventricular node, atrioventricular nodal artery, membranous septum, muscular atrioventricular sandwich (previously called the “muscular atrioventricular septum”), atrial septum, ventricular septum, aortic valvar complex, mitral valvar attachment, and tricuspid valvar attachment are associated with the inferior pyramidal space. We previously revealed its 3‐dimensional live anatomy using multidetector‐row computed tomography. Moreover, the 3‐dimensional understanding of the anatomy in association with the cardiac contour is important from the viewpoints of clinical cardiac electrophysiology. The purpose of this article is to demonstrate extended findings regarding the clinical structural anatomy of the inferior pyramidal space, which was reconstructed in combination with the cardiac contour using multidetector‐row computed tomography, and discuss the clinical implications of the findings.     

Comparison of two in vivo models for prostate cancer: Orthotopic and intratesticular inoculation of LNCaP or PC-3 cells

BACKGROUND: The critical events in the clinical course of prostate cancer are the occurrence of metastasis and the induction of the hormone-refractory status of the disease. In order to investigate the factors responsible for these events, we need appropriate in vivo models. MATERIALS AND METHODS: Orthotopic and intratesticular models were created by the injection of LNCaP cells or PC-3 cells into the prostate or testis of severe combined immunodeficient mice. RESULTS: LNCaP cells in the intratesticular model showed a higher incidence of tumor formation and lymph node metastasis when compared with those in the orthotopic model, while PC-3 cells were highly tumorigenic and metastastic in both models. A high concentration of androgens might play a role in tumor aggressiveness of LNCaP cells, given that enhanced mRNA expressions of integrin alphaV and vascular endothelial growth factor was induced by dehydrotestosterone administration in vitro. The high expression of metastasis-related genes, including the urokinase plasminogen activator system, metalloproteinases and vascular endothelial growth factor-C, might be attributed to the high metastatic potential in both models. Interestingly, testicular xenografts of LNCaP cells were able to survive on the subcutis back of castrated male mice as well female mice. CONCLUSIONS: Intratesticular models of prostate cancer appear to be suitable for studying the mechanisms of metastasis and for evaluating various treatment strategies.     

Intestinal-type mucinous adenocarcinoma arising from the prostatic duct

We present a case of mucinous adenocarcinoma of intestinal type arising from the prostatic duct in a 72-year-old Japanese man. The patient presented with macroscopic hematuria. Cystourethroscopy exhibited a mucus deposit at the 5 o'clock position of the verumontanum portion. A transurethral biopsy specimen revealed mucinous adenocarcinoma. A radical retropubic prostatectomy was performed. In the prostatectomy specimen, the cancer lesion mainly showed intraductal growth in the prostatic ducts with scattered mucin lakes in the prostatic stroma. There were no abnormalities in the urethral epithelium. The cancer cells resembled the intestinal epithelium rather than either the prostatic duct or the acinar epithelium, which showed diffusely positive immunohistochemical staining for carcinoembryonic antigen, but showed negative staining for prostate-specific antigen. Therefore, these findings suggest mucinous adenocarcinoma of intestinal type arising from the prostatic duct. A number of cases with mucinous adenocarcinoma arising from the prostatic urethra resembling the present case have been reported, but this is the first known case of carcinoma arising from the prostatic duct.     

Adenosine-Sensitive Atrial Reentrant Tachycardia Originating from the Atrioventricular Nodal Transitional Area

Adenosine-Sensitive AT from AVN Area. Introduction : Atrial tachycardia shows wide variations in its electrophysiologic properties and sites of origin. We report an atrial tachycardia with ECG manifestations and electrophysiologic characteristics similar to an atypical form of AV nodal reentrant tachycardia (AVNRT).
Methods and Results : This supraventricular tachycardia was observed in 11 patients. It was initiated by atrial extrastimulation with an inverse relationship between the coupling interval of an extrastimulus and the postextrastimulus interval. Its induction was not related to a jump in the AH interval, and its perpetuation was independent of conduction block in the AV node. Ventricular pacing during tachycardia demonstrated AV dissociation without affecting the atrial cycle length. A very small dose of adenosine triphosphate (mean 3.9 ± 1.2 mg) could terminate the tachycardia. The earliest atrial activation during tachycardia was recorded at the low anteroseptal right atrium with a different intra-atrial activation sequence from that recorded during ventricular pacing, where the tachycardia was successfully ablated in 9 of 10 attempted patients. Bidirectional AV nodal conduction remained unatttched after successful ablation.
Conclusion : There may he an entity of adenosine-sensitive atrial tachycardia probably due to focal reentry within the AV node or its transitional tissues without involvement of the AV nodal pathways. This tachycardia can he ablated without disturbing AV nodal conduction from the right atrial septum.     

Echo-Doppler measurements of portal vein and superior mesenteric artery blood flow in humans: Inter- and intra-observer short-term reproducibility

The reproducibility of echo-Doppler measurements of portal vein and superior mesenteric artery blood flow has not been extensively studied. In the present study, two groups of subjects were examined to test inter- and intra-observer reproducibility. Each study population consisted of 15 non-portal hypertensive and 15 portal hypertensive subjects. With a standardized technique, the cross-sectional area and velocity of blood flow in the portal vein and superior mesenteric artery were recorded in triplicate by skilled operators. The flow volume of each vessel was calculated by multiplying the cross-sectional area by the velocity of blood flow. The measurements were performed in a blind fashion over a 60 min period. The reproducibility of measurements was assessed by calculation of intraclass correlation coefficients and coefficients of variation. The intra-observer intraclass correlation coefficient was 0.77 for portal vein blood flow and 0.84 for superior mesenteric artery blood flow, suggesting good reproducibility. The intra-observer coefficient of variation was 11 and 9%, respectively. In contrast, the interobserver intraclass correlation coefficient was calculated to be 0.49 for portal blood vein blood flow and 0.57 for superior mesenteric artery blood flow, indicating fair reproducibility. In addition, the interobserver coefficients of variation were calculted to be 20 and 18%, respectively. These data suggest that intra-observer reproducibility in echo-Doppler measurements of portal vein and superior mesenteric artery blood flow is acceptable but inter-observer reproducibility is not. Examination by a single operator, rather than multiple operators, is therefore advisable. Even when measurements are performed by a single investigator an approximate variance of 10% in the measurement in a single subject should be expected.     

Successful renal transplantation in the right iliac fossa 2 years after serious deep venous thrombosis in a patient with systemic lupus erythematosus

Deep venous thrombosis (DVT) possibly occurs in the perioperative period, and induces serious complications such as a pulmonary embolism. On the other hand, allograft renal vein thrombosis leads to a high incidence of graft loss. We experienced a case in which a serious DVT occurred prior to renal transplantation; however, a successful renal transplantation in the right iliac fossa was performed after 2 years of anticoagulant therapy. It is suggested that the external iliac vein even after suffering from DVT can be anastomosed to an allograft vein successfully, when enough blood fl ow or a lower venous pressure is confirmed. However, one should be aware of the risk factors and the adequate management of thrombosis in renal transplantation because of the serious complications of DVT and the poor prognosis of allograft vein thrombosis.     

Pacemaker Syndrome Induced by the Mode Switching Algorithm of a DDDR Pacemaker

A patient with marked first-degree AV block and a DDDR pacemaker presented with a history of paroxysmal narrow QRS tachycardia, subsequently identified as sinus tachycardia (with a very long PR interval), causing a clinical problem similar to pacemaker syndrome because of loss of AV synchrony. The latter resulted from an excessively long postventricular atrial refractory period (PVARP) that prevented sensing of sinus P waves. The unfavorable hemodynamics caused reflex sinus tachycardia. The long PVARP was mandated by the mode switching algorithm of this particular device and was automatically set according to the selected tachycardia detection rate. The patient became asymptomatic when the mode switching function was turned off and the PVARP shortened.     

Clinical efficacy of an α1A/D-adrenoceptor blocker (naftopidil) on overactive bladder symptoms in patients with benign prostatic hyperplasia

AIM: We evaluated the efficacy of an alpha1a/d blocker, naftopidil, on storage symptoms in patients with benign prostatic hyperplasia (BPH), using frequency/volume charts (FVC). METHODS: A total of 81 patients with BPH (52-91 years, mean age 69.0 years) were studied. The inclusion criteria were: (i) one or more episode(s) of urinary urgency/day; (ii) a score of eight or more points on the International Prostate Symptom Score (I-PSS); and (iii) three or more points in any of the scores for three items (frequency, nocturia, and urgency) of the I-PSS. The patients received 50-75 mg/day of naftopidil for 6 weeks. All the patients were examined for 2-day FVC before and after the administration of naftopidil. I-PSS, quality of life index, and uroflowmetry were also evaluated. RESULTS: Total I-PSS decreased from 19.1 to 10.5 points (P < 0.0001), with significant improvement of both storage and voiding symptom scores (P < 0.0001, both). The score for urgency decreased from 3.1 to 1.4 (P < 0.0001). Daytime and night-time frequency decreased from 9.3 to 8.0 (P < 0.0001) and from 2.7 to 2.0 (P = 0.0009), respectively. Mean volume/void increased from 174.0 to 188.6 mL (P = 0.0453). Nocturia decreased from 3.2 to 2.3 (P < 0.0001) in 40 patients who suffered from nocturia two times or more. Notably, significant improvement of nocturia was observed in the patients both with and without nocturnal polyuria (P = 0.0006 and 0.0135, respectively). CONCLUSION: The alpha1a/d blocker naftopidil improves not only voiding symptoms but also storage symptoms, and is effective for nocturia in patients with BPH regardless of the existence of nocturnal polyuria.