Practical Aspects of Rate Adaptive Atrial (AAI,R) Pacing: Clinical Experiences in 44 Patients

Forty-four patients with sinus node disease and chronotropic incompetence but no evidence of AV conduction disturbances were treated with rate adaptive atriul (AAI,R) pacemakers. Medtronic Activitrax and Siemens Sensolog activity sensing single chamber pulse generators were used. Twentyfour patients (55%) had the bradycardia-tachycardia syndrome. The mean folloiw-up time is 20 ± 14 months (range 1–48, median 17 months). All patients remain alive. Two patients were reoperated upon for lead problems without change of pacing mode. One patient developed symptomatic: srecond-degree Wenckebach block during follow-up, and received a DDD,R system. Although 22 of the patients were treated with antiarrhythmic drugs postoperatively, no further cases of significant AV conduction disturbances were seen. During rapid atrial pacing, exercise-induced enhancement of AV conduction was a consistent finding, although less pronounced in patients treated with beta-blocking drugs. One patient developed permanent atrial fibrillation with an adequate ventricular rate. By systematic reprogramming procedures, QRS complex sensing through the atrial electrode could be demonstrated in 25 patients (23/28 with unipolar and 2/16 with bipolar leads). it could be counteracted effectively by pulse generator program selection in all cases. Forty-two of 44 patients (95%) remain in AAI,R pacing with normal function, Rate adaptive atrial pacing can be successfully applied in this patient group.     

Acute myocardial infarction due to thrombus formation in congenital coronary artery fistula

A young female patient developed acute myocardial infarctionduring physical exercise. Coronary arteriography in the acutephase demonstrated a coronary fistula originating from the leftcoronary main trunk and communicating with the right atrium.Several branches of the left coronary artery were obstructedby thrombotic material originating from the fistula, causingan acute myocardial infarction.     

A case of Behçet's disease aggravated by gingival infection with methicillin-resistant Staphylococcus aureus

We report a case of Behcet's disease aggravated by gingivitis and carious teeth infected with methicillin-resistant Staphylococcus aureus. Recurrent severe ulcers in the mouth, and on the genitalia and legs were closely linked with the infection, and dramatically improved after extraction of the carious teeth and administration of systemic vancomycin hydrochloride.     

Characteristics of masticatory movement in relation to inclination of occlusal plane

summary The relationship between masticatory movement and the inclination of the occlusal plane in sagittal plane was analysed in 41 young adults. It was found that the occlusal plane and the masticatory closing path were consistent in maintaining an almost perpendicular relationship with each other, regardless of the variation in inclination of the occlusal plane. This finding can be explained by the observation that the timing of the balancing-side condylar translation during closure correlated with the inclination of the occlusal plane. The inclination of the occlusal plane also influenced the masticatory closing pattern in the sagittal plane. Anterior convex closure patterns dominated when the occlusal plane inclined in the anterior direction. In contrast, the majority of posterior convex closure patterns were induced by the posteriorly inclined occlusal plane. The appearance of these types seems to reflect a harmonious relationship between the inclination of the occlusal plane, tooth guidance, and other central and peripheral control. The correlation between the inclination of the occlusal plane and masticatory closing movement could serve as the functional background for the significance of the occlusal plane.     

Importance of mechanical damage to urinary red blood cells by the glomerular basement membrane

The reasons for morphological changes of urinary red blood cells (RBC) in patients with glomerulonephritis are still controversial. In order to evaluate the importance of mechanical damage by the glomerular basement membrane (GBM), we examined urinary RBC taken from the patients with two different diseases which have characteristic GBM changes. Urinary RBC taken from 20 patients with Alport syndrome and nine with thin GBM disease were examined using a scanning electron microscope. Nineteen out of the 20 patients (95.0%) with Alport syndrome showed ‘glomerular type’, while five of the nine patients (55.6%) with thin GBM disease showed ‘glomerular type’. These results suggest that more complicated GBM abnormalities cause more severe RBC distortion. Therefore, we conclude that mechanical damage by the GBM may be the major factor in dysmorphism of urinary RBC.     

Electrophysiological and Anatomical Substrates for Late Potential Recorded by Signal Averaging in Seven-Day-Old Myocardial Infarction in Dogs

A filtered QRS (fQRS) was recorded by signal averaging in 7-day-old myocardial infarction (MI) in dogs to detect late potential (LP). The criteria for the LP included a duration of fQRS (D) greater than or equal to 60 msec and a voltage in the last 15 msec (V15) less than or equal to 10 microV. These parameters were determined from the control data from 15 dogs without infarction (D: 45 to 60 msec and V15: 12.0 to 83.6 microV). On the seventh day of infarction, the D had increased from 53.5 +/- 4.7 to 62.2 +/- 9.6 msec (P less than 0.05) and the V15 decreased from 38.6 +/- 19.5 to 18.4 +/- 16.0 microV (P less than 0.01). Of 23 dogs, 14 met the LP criteria (group A) and 9 did not (group B). Sustained ventricular tachycardia (SVT) was induced in 12 group A dogs and in none of the group B dogs. The delayed epicardial activation (DEA) was recorded after the end of QRS at 5.1 +/- 4.7 sites in group A dogs and 1.3 +/- 1.8 sites in group B dogs (P less than 0.05). The maximum value of epicardial activation time was more prolonged in group A than in group B (70.0 +/- 28.3 vs 44.4 +/- 9.8 msec, P less than 0.01). The area of MI was more extensive in dogs with DEA than those without (24.9 +/- 5.8% vs 10.3 +/- 9.0% of the total left ventricular weight, P less than 0.01). In 72 of 90 sites with DEA, the thickness of the surviving epicardial muscle was less than or equal to 1 mm. The sensitivity and specificity of the criteria for LP in detecting DEA were 71.4% and 55.6%, and 100% and 81.8% for predicting inducibility of SVT. It was thus concluded that LP, reflected the DEA, was identified from infarct areas of slow conduction within a reentry circuit of SVT.     

Diagnosis of small hepatocellular carcinoma by computed tomography: Correlation of CT findings and histopathology

The diagnostic value of computed tomography (CT) scans in small hepatocellular carcinoma (HCC) (less than 5 cm) was studied in 82 patients. Dynamic scan was also made in 66 of them. Combined unenhanced and enhanced scans detected 87% of the lesions greater than 2 cm, but the detection rate was only 25% for lesions less than 1.5 cm. Diagnostic failure was due to isodensity of the mass and to technical artefacts. Diagnosis of the surrounding capsule and internal septa (partition) and demonstration of the typical pattern of density enhancement by dynamic scan proved useful in differentiating HCC from secondary cancers. On unenhanced CT, the density of the interior was subject to the histological changes of tumour such as bleeding, necrosis and fatty metamorphosis. Similarly, enhanced CT showed density changes suggestive of these histological changes. Dynamic scan proved particularly useful for lesions less than 3 cm because the typical density enhancement was frequently demonstrated in the arterial phase. It was concluded that unenhanced CT combined with dynamic scan has a high diagnostic value in small HCC and reflects histological changes.     

HLA‐haploidentical nonmyeloablative stem cell transplantation: induction to tolerance without passing through mixed chimaerism

There are few reports of unmanipulated HLA‐haploidentical nonmyeloablative stem cell transplantation (NST) using only pharmacological acute graft‐vs.‐host disease (GVHD) prophylaxis. We present here a successful case of unmanipulated HLA‐haploidentical NST for mediastinal large B cell lymphoma that was resistant to autologous peripheral blood stem cell transplantation (PBSCT). The conditioning regimen consisted of fludarabine, busulfan and rabbit anti‐T‐lymphocyte globulin (ATG) in addition to rituximab. GVHD prophylaxis was performed using tacrolimus and methylprednisolone 1 mg/kg. The patient had rapid engraftment, with 100% donor chimaerism in the lineages of both T cells and granulocytes on day +12, but developed no GVHD clinically. The patient is still in complete remission past day +1020, with no sign of chronic GVHD without receiving immunosuppressive agents. HLA‐haploidentical NST may be performed without utilizing mixed chimaerism.     

Human herpesvirus-6-associated exanthema in a patient with acute lymphocytic leukaemia

We report the first case of human herpesvirus-6 (HHV-6) associated exanthema in a patient with acute lymphocytic leukaemia (ALL). We analysed DNA extracted from an exanthematous lesion using the polymerase chain reaction (PCR). DNA was positive for HHV-6 but negative for herpes simplex virus, varicella zoster virus, and cytomegalovirus. Immunohistochemical staining of the skin with monoclonal antibody against HHV-6 confirmed the infection. The possibility of HHV-6 infection should be considered when an atypical skin rash is seen in patients with ALL.