• 2018-07
  • 2018-10
  • 2018-11
  • 2019-04
  • 2019-05
  • br Study limitations br Introduction


    Study limitations
    Introduction The spread of basic life support (BLS), including use of automated external defibrillators in the general public, may increase the chance of survival from sudden cardiac death (SCD). Survivors usually have underlying cardiac diseases, such as coronary artery disease, cardiomyopathy, valvular heart disease, or myocardial channel disease. Ventricular fibrillation (VF) is one of the important causes of SCD [1,2] in patients with coronary vasospasm. The Guidelines for Risks and Prevention of Sudden Cardiac Death 2010 (Guideline 2010) [3] stated that fatal ventricular arrhythmias, including VF, in patients with variant Erismodegib should be prevented by intensive medical therapy against coronary vasospasm. However, there are some patients who are refractory to intensive medical therapy and are at high risk of recurrent VF [4]. Although there have been reports that ICD is useful for patients with coronary vasospasm complicated by VF [5–8], implantation of ICD in these patients remains controversial and is regarded as Class 2b in the Guideline 2010. In this study we examined 19 patients with coronary vasospasm complicated with VF and considered the effective treatment and prevention of its recurrence.
    Discussion We defined the positive response to the ACh provocation test only by the results of coronary angiography, which did not agree with the Guidelines for Diagnosis and Treatment of Patients with Coronary Spastic Angina (JCS 2008) [9], because we do not believe that coronary vasospasm always leads to chest pain and/or ST-segment changes [10]. Although the ACh provocation test is useful for diagnosis of multiple coronary vasospasm [9], we performed the test only in the LCA in most of the patients because the avoidance of VF recurrence caused by multiple coronary vasospasms during the test, in accordance with the fact that site and degree of coronary spasm can migrate [10], was more important than diagnosis of multiple spasms. Patients with coronary vasospasm and VF have heterogeneous clinical manifestations, such as ST-segment elevation or depression, variant angina [4,5] or silent myocardial ischemia [1,11], and negative results of EPS [2] or positive results even without coronary spasm [12]. Preparations for VF recurrence include education in BLS, especially for family members and others close to the patients, and ICD implantation. Although there are reports of limitations of ICDs, such as inappropriate discharge [13] and complication of VF storm and pulseless electrical activity [5,14], there are also reports of successful combination therapy with medical treatment, stent implantation, and/or ICD implantation [5–8] The fact that 1 of 13 patients with ICD implantation was successfully converted from VF recurrence encourages us to prepare for the worst, i.e., recurrence of VF under intensive medical therapy, by taking all possible measures, including ICD implantation.
    Conflict of interest
    Introduction Venipuncture is an essential technique that is used for pacemaker implantation procedures. In the past, subclavian venipuncture was utilized; however, this technique was often associated with problems such as pacemaker lead breakage [1]. In recent pacemaker implantation procedures, techniques such as the cut-down method, ultrasound-guided puncture, and extrathoracic puncture have been primarily employed. We perform pacemaker lead insertions by extrathoracic puncture; however, the patients\' body movements can displace the targeted vein from the area into which the imaging contrast agent has been injected. Failed punctures cause edema around the puncture site, spasm, or venous collapse due to bleeding, which may make another puncture impractical. To overcome these problems, we report our novel technique for pacemaker lead insertion.
    Patients and methods From April 2007 through March 2011, we performed 35 new dual chamber pacemaker implantation procedures. This study compared a conventional puncture group (from April 2007 through March 2009; Group A) with a catheter-guided puncture group (from April 2009 through March 2011; Group B; Table 1). In the conventional puncture group (Group A), a contrast agent was infused into the peripheral veins of the left forearm while imaging in the 30° left anterior oblique (LAO30) position. After creating a pocket for the pacemaker in the left side of the body, we performed extrathoracic puncture while imaging in the LAO30 position. In the catheter-guided puncture group (Group B), prior to transvenous insertion of the pacemaker lead, a JR40 catheter was inserted into the right femoral vein, through which a contrast agent was infused into the left axillary or left subclavian veins with LAO30 position imaging. During this process, the inserted JR40 catheter remained in situ. After creating a pocket for the pacemaker in the left side of the body, we performed catheter-targeted extrathoracic puncture with LAO30 position imaging (Fig. 1). The catheter was left indwelling until a successful puncture was confirmed. In patients that were likely to have venous collapse due to dehydration, we performed the puncture while ensuring that the vein was dilated by 20-mL physiological saline flushes through the JR40 catheter (Fig. 2). We analyzed procedure time and procedure-related complications in each group. Procedure time was defined as the time from skin incision to closure in each pacemaker implantation procedure.