Medium-term results of percutaneous transluminal balloon aortic valvuloplasty with Inoue balloon catheter for congenital aortic stenosis

Although percutaneous transluminal balloon aortic valvuloplasty (PTAV) has been performed for congenital aortic stenosis in infants and children for several years, its efficacy and the associated aortic regurgitation (AR) have not been widely discussed. Percutaneous transluminal balloon aortic valvuloplasty using an Inoue balloon catheter was performed for congenital aortic stenosis in 12 patients (4–16 years old) in this study. The systolic aortic valve pressure gradient ranged from 42 to 111 mmHg before PTAV and became < 50 mmHg immediately after PTAV in 10 cases (83%). Eight of these 10 patients had no increase in the gradient during subsequent observation for a period of 9–40 months. Aortic regurgitation increased immediately after PTAV in nine cases (75%). It increased from grade 1 to grade 2 in eight cases and from grade 1 to grade 3 in one patient; no significant enlargement of the left ventricular end-diastolic diameter and no significant change in the left ventricular end-diastolic pressure (LVEDP) or the cardiac index was observed during follow-up in these patients. There was a correlation between the diameter of the balloon and efficacy; an appropriate diameter was considered to be about 90% of the aortic annular diameter. Changes in the hemodynamic parameter after PTAV with an Inoue balloon were small in most patients and this procedure is considered to be a treatment that should be attempted prior to surgery for congenital aortic stenosis.     

Stromal cell-derived factor-1α improves infarcted heart function through angiogenesis in mice

BACKGROUND: Local delivery of stromal cell-derived factor-1alpha (SDF-1) has been demonstrated to improve hind limb ischemia through enhanced neovascularization in animals. It was hypothesized that local administration of SDF-1 also contributes to neovascularization of ischemic heart. METHOD: Acute myocardial infarction was created by left coronary artery ligation in C57BL/6J mice. Immediately after infarction induction, mice were treated by injection directly into the center of ischemic myocardium either with saline (control group) or SDF-1 (SDF-1 group). Cardiac function was measured on echocardiogram 2 and 4 weeks after infarction. On week 4 mice were killed to evaluate infarction size and capillary vessel density. To determine the contribution of bone marrow cells to angiogenesis, the same procedures were performed on C57BL/6J chimeric mice reconstituted with green fluorescent protein-positive bone marrow cells. RESULTS: Fractional shortening was greater in the SDF-1 group at 4 weeks (0.31 +/- 0.06% vs 0.23 +/- 0.03%, P = 0.037). The infarct area was smaller in the SDF-1 group compared to the control group (9.31 +/- 2.76% vs 18.07 +/- 5.69%, P = 0.028). Green fluorescent protein-positive cells accumulated predominantly at the peri-infarction site, and were located with the capillary vessels. Capillary vessel density was significantly increased in the SDF-1 group (13.08 +/- 4.11 vessels/mm(2) vs 34.50 +/- 7.59 vessels/mm(2), P = 0.014). CONCLUSIONS: SDF-1 protects against deterioration of cardiac function after acute myocardial infarction by promoting angiogenesis. The safety and long-term prognosis of this treatment remains to be determined.     

Hybrid Therapy of Radiofrequency Catheter Ablation and Percutaneous Transvenous Mitral Commissurotomy in Patients With Atrial Fibrillation and Mitral Stenosis

AF Ablation and PTMC. Background: The rhythm control of atrial fibrillation (AF) associated with mitral stenosis (MS) is often difficult using antiarrhythmic drugs (AADs), even after a percutaneous transvenous mitral commissurotomy (PTMC). Few studies have examined the efficacy and safety of simultaneously performing radiofrequency catheter ablation (RFCA) and a PTMC in patients with MS and AF. Methods: Twenty consecutive patients with drug‐resistant AF and rheumatic MS underwent RFCA combined with a PTMC (n = 10; persistent AF‐8, long‐lasting [>1 year] persistent AF‐2; RFCA group) or transthoracic direct cardioversion (DC) following a PTMC (n = 10; persistent AF‐7, long‐lasting persistent AF‐3; DC group). In all patients, the mitral valve morphology was amenable to a PTMC, and more than 2 AADs had been ineffective in maintaining sinus rhythm (SR). In the RFCA group, a segmental pulmonary vein isolation (PVI) was performed in the initial 5 patients, and an extensive PVI was performed in the remaining 5. Results: During a mean follow‐up period of 4.0 ± 2.7 years, 8 patients (80%) in the RFCA group were maintained in SR, as compared to 1 (10%) in the DC group (hazard ratio, 0.16; 95% confidence interval, 0.03 to 0.75; P = 0.008 by the log‐rank test). The prevalence of the concomitant use of class I and/or class III AADs was comparable between the 2 groups (P = 0.70). No complications occurred during the procedure or follow‐up period in either group. Conclusions: The hybrid therapy using RFCA and a PTMC was safe and feasible, and significantly improved the AF free survival rate compared to DC following a PTMC. (J Cardiovasc Electrophysiol, Vol. 21, pp. 284–289, March 2010)     

Long-Term Results of Cryoablation with a New Cryoprobe to Eliminate Chronic Atrial Fibrillation Associated with Mitral Valve Disease

The purpose of this study was to examine the performance of a new cryoprobe in the treatment of chronic atrial fibrillation (AF) associated with mitral valve disease. The study included 66 patients undergoing mitral valve replacement. The mean AF duration was 9.0 ± 9.0 years and mean left atrial (LA) was diameter 57 ± 10 mm. Cryoablation (−60°C) was applied to four pulmonary vein (PV) orifices over 2–3 minute. The spherical tip (2-cm in diameter) of the cryoprobe is capable of ablating the left atrium near the PV, as well as the PV ostium with a single cryoablation. After cryoablation, mitral valve surgery or a combined surgical procedure were performed in 66 patients. There were no intraoperative complications. Sinus rhythm was restored in 60 patients (91%) immediately after the operation. Recurrent AF was treated with antiarrhythmic drugs and/or direct current cardioversion in 43 patients (72%). At discharge, 48 patients (72%) were in sinus rhythm. During a mean follow-up period of 31 ± 16 months, 40 patients (61%) were in sinus rhythm with (29) or without antiarrhythmic drugs (11). In patients in sinus rhythm at the end of the follow-up period, the duration of preoperative AF duration was significantly shorter (P < 0.05) and the preoperative LA diameter and cardiothoracic ratio were significantly smaller than in patients who were in AF (both for P < 0.005). Using this new cryoprobe, sinus rhythm was restored and maintained in 61% of patients with chronic AF and mitral valve disease with a 12–15 minute cryoablation procedure.     

Verapamil-Sensitive Left Anterior Fascicular Ventricular Tachycardia: Results of Radiofrequency Ablation in Six Patients

Verapamil-Sensitive Left Anterior Fascicular VT. Introduction: Verapamil-sensitive left ventricular tachycardia (VT) with a right bundle branch block (RBBB) configuration and left-axis deviation bas been demonstrated to arise from the left posterior fascicle, and can be cured by catheter ablation guided by Purkinje potentials. Verapamil-sensitive VT with an RBBB configuration and right-axis deviation is rare, and may originate in the left anterior fascicle. Methods and Results: Six patients (five men and one woman, mean age 54 ± 15 years) with a history of sustained VT with an RBBB configuration and right-axis deviation underwent electrophysiologic study and radiofrequency (RF) ablation. VT was slowed and terminated by intravenous administration of verapamil in all six patients. Left ventricular endocardial mapping during VT identified the earliest ventricular activation in the anterolateral wall of the left ventricle in all patients. RF current delivered to this site suppressed the VT in three patients (ablation at the VT exit). The fused Purkinje potential was recorded at that site, and preceded the QRS complex by 35, 30, and 20 msec, with pace mapping showing an optimal match between the paced rhythm and the clinical VT. In the remaining three patients, RF catheter ablation at the site of the earliest ventricular activation was unsuccessful. In these three patients, Purkinje potential was recorded in the diastolic phase during VT at the mid-anterior left ventricular septum. The Purkinje potential preceded the QRS during VT by 66, 56, and 63 msec, and catheter ablation at these sites was successful (ablation at the zone of slow conduction). During 19 to 46 months of follow-up (mean 32 ± 9 months), one patient in the group of ablation at the VT exit bad sustained VT with a left bundle branch block configuration and an inferior axis, and one patient in the group of ablation at the zone of slow conduction experienced typical idiopathic VT with an RBBB configuration and left-axis deviation. Conclusion: Verapamil-sensitive VT with an RBBB configuration and right-axis deviation originates close to the anterior fascicle. RF catheter ablation can be performed successfully from the VT exit site or the zone of slow conduction where the Purkinje potential was recorded in the diastolic phase.     

Retrograde Supernormal Conduction in Concealed Accessory Atrioventricular Pathway Following Catheter Ablation

Supernormal Conduction in Concealed Kent Following Ablation. A case is presented of a 63-year-old woman with a concealed accessory pathway that exhibited retrograde supernormal conduction after radiofrequency catheter ablation. Although ventricular pacing at a slow rate revealed no retrograde conduction over the accessory pathway following ablation, the tachycardia recurred 15 months later. During ventricular pacing there was retrograde 1:1 conduction over the accessory pathway at a fast rate while there was intermittent VA dissociation with rare retrograde conduction at the slower rate. Ventricular extrastimulus testing demonstrated a supernormal conduction zone of the coupling interval. Thus, accessory pathways may exhibit supernormal conduction after catheter ablation. Pacing should be performed at both slow and fast rates to confirm the presence of conduction block following ablation.     

Tamoxifen Therapy for Premenopausal and Postmenopausal Japanese Females with Advanced Breast Cancer

The antiestrogenic agent tamoxifen was orally administered to74 Japanese patients with advanced breast cancer, with the followingresults: (1) Administration of tamoxifen resulted in a totalresponse rate of 43.4% (Marked response 23.0%, Moderate response20.3%), equivalent to 31.1% (Complete response + Partial response)by the criteria of the International Union against Cancer. (2)With regard to metastatic lesions, the response rate was 44.4%for soft tissue, 28.0% for skeletal, and 44.4% for pulmonaryand pleural metastases. (3) Tamoxifen induces very slight sideeffects compared to the commonly used androgens, and it hasno androgenic action. (4) Tamoxifen was shown to be effectivenot only in postmenopausal patients but also in pre menopausalpatients. (5) The appropriate dose of tamoxifen for Japanesepatients with advanced breast cancer is considered to be 20mg/day. (6) When patients with recurrent cancer were treated,many who responded to previous endocrine therapy or treatmentwith other anticancer drugs also responded well to tamoxifentherapy.     

Chemotherapy with Mitomycin-C and Cyclophosphamide Adjuvant to Surgery for Breast Cancer

The effect of adjuvant chemotherapy on breast cancer was studiedin two trials. In the first, mitomycin-C was administered intravenouslyto 203 patients and cyclophosphamide intravenously or orallyto 72 patients, within four weeks after radical mastectomy.The results were evaluated by compairing the recurrence-freerates of these patients with those of 556 patients who receivedsurgery alone. The effect of postsurgical adjuvant chemotherapy on the recurrence-freerate was statistically significantly better than that of surgeryalone when one or two axillary lymph nodes were involved inmetastasis, possibly because of the suppressive effect of chemotherapyon the establishment of hematogeneous metastases. With no orthree to seven metastases, the recurrence-free rate for patientsreceiving surgical treatment combined with adjuvant chemotherapywas higher than that for those with surgery alone, but the differencewas not statistically significant. In advanced cases havingeight or more axillary lymph node metastases, chemotherapy appearedsignificantly to reduce the recurrence- free rate compared withsurgery alone. This is possibly attributable to deteriorationin host immunity caused by chemotherapy being administered immediatelyafter surgery and affecting the host's defense mechanisms. In the second trial, which is still in progress, oral cyclophosphamidewas administered to 172 patients, 150 mg daily, for 34 daysfrom the seventh day after surgery. When compared with 179 patientshaving surgery alone, this chemotherapy increased the four-yearrecurrence-free rate in patients with no axillary lymph nodemetastases and the two-year recurrence-free rate in patientswith eight or more axillary lymph node metastases.