Subcutaneous air entrapment after subcutaneous implantable cardioverter defibrillator implantation evaluated by computed tomography.

BACKGROUND: Inappropriate shock (IAS) caused by subcutaneous air entrapment (AE) in an early period after subcutaneous implantable cardioverter defibrillator (S-ICD) implantation has been reported, however, no detailed data on air volume are available. We evaluated the subcutaneous air volume after implantation and its absorption rate one week after implantation. METHODS: Patients who underwent S-ICD implantation in our hospital received chest CT scans immediately after implantation and followed up 1 week later. The total subcutaneous air volume, air around the generator, the distal electrode, and the proximal electrode within 3 cm were calculated using a three-dimensional workstation. Fat areas at the level of the lower edge of the generator were also analyzed. RESULT: Fifteen patients received CT immediately after implantation. The mean age was 45.6 ± 17.9 (66.7% of men), and the mean body mass index was 24.3 ± 3.3. The three-incision technique was applied in seven patients and two-incision technique was in the latter eight patients. The mean total subcutaneous air volume was 18.54 ± 7.50 mL. Air volume around the generator, the distal electrode, and the proximal electrode were 11.05 ± 5.12, 0.72 ± 0.72, and 0.88 ± 0.87 mL, respectively. Twelve patients received a follow-up CT 1 week later. The mean total subcutaneous air was 0.25 ± 0.45 mL, showing a 98.7% absorption rate. CONCLUSION: Although subcutaneous air was observed in all patients after S-ICD implantation, most of the air was absorbed within 1 week, suggesting a low occurrence of AE-related IAS after a week postoperation.

Significance of Ventricular Arrhythmia Based on Stored Electrogram Analysis in a Pacemaker Population.

The incidence of ventricular arrhythmia in patients with an implanted pacemaker is not yet known. The aim of this study was to analyze non-sustained ventricular tachycardia (NSVT) episodes based on stored electrograms (EGM) and determine the occurrence rate and risk factors for NSVT in a pacemaker population.This study included 302 consecutive patients with a dual-chamber pacemaker. A total of 1024 EGMs stored in pacemakers as ventricular high-rate episodes were analyzed. The definition of NSVT was ≥ 5 consecutive ventricular beats at ≥ 150 bpm lasting < 30 seconds.In baseline, most patients (94.8%) had ≥ 60% left ventricular ejection fraction. Of 1024 EGMs, 420 (41.0%) showed appropriate NSVT episodes, as well as premature atrial contractions, atrial tachyarrhythmia, or atrial fibrillation with a rapid ventricular response, whereas other EGMs did not show an actual ventricular arrhythmia. On EGM analysis, during a mean follow-up period of 46.1 months, NSVT occurred one or more times in 82 patients (33.1%). On multivariate analysis, ≥ 50% right ventricular pacing was an independent risk factor for NSVT (odds ratios, 4.519; P < 0.001), but NSVT was not associated with increased all-cause mortality.Moreover, in the pacemaker population, ≥ 50% right ventricular pacing is an independent risk factor for NSVT; however, NSVT was not associated with increased all-cause mortality because of the preserved left ventricular function.

Synthesis and Stereochemical Revision of the Aromatic Polyketide NFAT-133.

NFAT-133, isolated from Streptomyces sp., is an immunosuppressive, antidiabetic, and antitrypanosomal aromatic polyketide with three contiguous stereocenters. The first enantioselective total synthesis of the proposed structure of NFAT-133 [(10R,11R,12S)-1] and its C10 epimer [(10S,11R,12S)-1] was achieved from a known aromatic ester (5) by a 10-step sequence that featured chiral auxiliary-directed asymmetric alkylation and the Evans asymmetric aldol reaction as the chirality-inducing steps. The 1H and 13C NMR data as well as the specific rotation value of natural NFAT-133 were not identical to those of the proposed structure, but were in good agreement with those of its C10 epimer. This led us to conclude that the absolute configuration of NFAT-133 should be revised to 10S, 11R, and 12S.

An Inappropriate Shock Case Early after Implantation of a Subcutaneous Cardiac Defibrillator by Subcutaneous Entrapped Air.

A 17-year-old woman was resuscitated from cardiac arrest due to ventricular fibrillation and was diagnosed with concealed long QT syndrome. She underwent subcutaneous implantable cardiac defibrillator (S-ICD) implantation at our hospital. The device electrogram immediately after implantation was normal. Four days after implantation, she received an inappropriate shock. The device interrogation revealed a continuous baseline shift and frequent oversensing for low amplitude signals, followed by a shock. A chest radiograph in the orthogonal view showed entrapped subcutaneous air surrounding the distal electrode. Entrapped subcutaneous air can cause inappropriate shocks in the early period after S-ICD implantation.

Characteristics and Prognosis of Pacemaker-Identified New-Onset Atrial Fibrillation in Japanese People.

BACKGROUND: The characteristics and prognosis of implanted pacemaker-identified new-onset atrial fibrillation (AF) in Japanese people has not been well evaluated.Methods and Results:A total of 395 consecutive patients with newly implanted pacemakers were retrospectively analyzed between January 2010 and December 2015 at Yokohama City University Hospital. Patients with a prior history of AF, VVI mode pacemaker, congenital heart disease, severe valvular heart disease, and cardiovascular surgery before pacemaker implantation were excluded. Among the remaining patients, 44 (21.3%) developed new AF during follow-up (mean follow-up, 1,115±651 days; range, 9-2,176 days). Patients with new-onset AF had a significantly higher CHADS2score (2.09±1.27 vs. 1.31±1.08, P<0.001) and CHA2DS2-VASc score (3.00±1.39 vs. 2.26±1.19, P<0.001) compared with those without new-onset AF. On Cox regression analysis only age at implantation was significantly correlated with new-onset AF. Interestingly, the incidence of hospitalization due to heart failure was significantly higher in the new-onset AF than in the without new-onset AF group. CONCLUSIONS: A total of 21.3% of pacemaker-implanted patients with high CHADS2and CHA2DS2-VASc scores developed new-onset AF during a mean follow-up of 3.1 years; and pacemaker-identified AF was associated with an increased risk of worsening heart failure.

Development of Atrioventricular Block and Diagnostic Value of Stored Electrograms in Patients With Sick Sinus Syndrome and Implanted Pacemaker.

BACKGROUND: The incidence of atrioventricular block (AVB) in pacemaker patients with sick sinus syndrome (SSS) is not yet known. The aim of this study was to analyze AVB episodes in SafeR mode based on stored electrograms (EGM), and determine the occurrence rate and risk factors for advanced AVB in a pacemaker population with SSS. METHODS AND RESULTS: The study included 50 consecutive patients with SSS without a history of advanced AVB who had a dual-chamber pacemaker programmed in SafeR mode. A total of 377 EGM stored in the pacemakers as AVB episodes fulfilling the second- or third-degree criterion were analyzed. Of 377 EGM, 73 EGM (19.4%) were appropriate episodes, whereas the other EGM did not show actual AVB, and showed atrial tachyarrhythmia, ventricular event in the blanking period, or premature atrial contractions with block. On EGM analysis, advanced AVB occurred in 9 patients (18%), and the occurrence rate was 11.7% per year. Moreover, on multivariate analysis ß-blocker use was an independent risk factor for advanced AVB (OR, 9.10; P=0.004). CONCLUSIONS: The occurrence rate of advanced AVB in patients with SSS is much higher than previously reported, and ß-blocker use is an independent risk factor for advanced AVB. SafeR is useful to detect latent AVB. Stored EGM, however, sometimes include inaccurately classified events.

Successful implantation of left ventricular lead for a cardiac resynchronization therapy defibrillator through a persistent left superior vena cava using the anchor balloon technique.

A 69-year-old woman was referred for upgrading implantable cardioverter defibrillator (ICD) to cardiac resynchronization therapy defibrillator (CRT-D) because of symptomatic heart failure due to dilated cardiomyopathy. Her electrocardiogram showed left bundle branch block and echocardiography showed severe left ventricular dysfunction. Venography confirmed the presence of persistent left superior vena cava (PLSVC), and occlusion of innominate vein and the coronary sinus (CS) ostium. We tried to insert the left ventricular (LV) lead through the PLSVC. Because the PLSVC was narrow, there was concern that insertion of the guiding catheter through the PLSVC might cause vascular damage. Therefore, we planned to implant the LV lead without a guiding catheter. Although the LV lead did not advance to the CS due to the acute angle, using a second wire (buddy wire system), the tip of the first wire was trapped by an inflated balloon delivered by a second wire (anchor balloon technique). This technique allowed us to reinforce the support of the other wire. The LV lead was easily advanced along with the fixed first wire and was delivered to the lateral vein of the CS. Thus, we successfully performed minimally invasive implantation of an LV lead through a PLSVC approach. .

Importance of pleural findings in patients with amyloid cardiomyopathy complicated with refractory pleural effusion.

A 76-year-old male was admitted to our hospital for progressive bilateral pleural effusion. Because of typical echocardiographic findings such as left ventricular (LV) hypertrophy, thickness of the mitral valve, and a granular sparkling appearance of the LV wall, amyloid cardiomyopathy was suspected. Regardless of up-titration of several diuretic agents, the bilateral pleural effusion did not improve. Because the histological findings of the right ventricular septum (direct-fast-scarlet staining) obtained by biopsy that demonstrated amyloid deposits in perivascular and pericellular lesions, amyloid cardiomyopathy was diagnosed. However, cardiac catheterization revealed normal right and left atrial pressure and normal right and left ventricular end-diastolic pressure. Therefore, hemodynamic deterioration was less likely to be the cause of persistent pleural effusion. Amyloid deposits were also detected in the pleural biopsy specimen, so pleural amyloidosis was diagnosed and may have played an important role in the refractoriness of the pleural effusion. .

Malignant solitary fibrous tumor of the pancreas: a case report.

BACKGROUND: Solitary fibrous tumors (SFTs) are rare tumors, mostly derived from connective tissue mesenchymal cells that arise from the pleura. There are very few reports of primary pancreatic SFT. Preoperative diagnosis is difficult owing to the lack of distinctive radiological findings. We report a case of pancreatic SFT with particularly rare malignant findings. CASE PRESENTATION: A 60-year-old man was referred to the hospital because of a right upper quadrant mass and abnormal liver function test results. Contrast-enhanced computed tomography (CT) showed a well-defined enhanced tumor measuring approximately 8 cm in the pancreatic head. Magnetic resonance imaging (MRI) showed T1WI hypointensity, T2WI hyperintensity, and DWI hyperintensity. The main pancreatic duct and common bile duct were dilated owing to obstruction by the tumor. The following tumor markers were mildly elevated: carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), SPan-1, and DUPAN-2. The histological diagnosis obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) was negative for pancreatic ductal carcinoma, malignant lymphoma and neuroendocrine tumor, suggesting the possibility of mesenchymal tumor, but the diagnosis was not confirmed. The patient was judged suitable for surgery and underwent subtotal stomach-preserving pancreatoduodenectomy with D2 lymph node dissection. On histopathological examination of the resected specimen, infiltrating spindle-shaped cells had proliferated, containing numerous mitotic figures, with necrotic findings inside the tumor. Immunostaining was positive for cluster of differentiation-34 (CD34), B cell CLL/lymphoma-2 (Bcl-2), and signal transducer and activator of transcription (STAT6). On the basis of these findings, a diagnosis of malignant pancreatic SFT was made. The patient remains free of recurrent disease after 12 months of follow-up without adjuvant therapy and he is being carefully followed up as an outpatient. CONCLUSIONS: We experienced a case of malignant pancreatic head SFT. Immunohistochemical staining of the extracted specimens was useful for diagnosis.

Successful screening of sleep-disordered breathing using a pacemaker-based algorithm in Japan.

BACKGROUND: Recent pacemakers with transthoracic impedance sensors have a specific algorithm identifying sleep apnea (SA). Our aim was to evaluate the algorithm in Japanese patients. METHODS: Consecutive patients implanted with a pacemaker with sleep apnea monitoring algorithm at our hospital were enrolled prospectively. After implantation, patients underwent polysomnography (PSG). The respiratory disturbance index measured by pacemaker (RDI-PM) was extracted in the morning after PSG. RESULTS: Forty-five patients were recruited; 78% of patients underwent overnight PSG completely, and among them RDI-PM was invalid for one patient. Then the analysis was performed in 34 patients. Moderate/severe SA (apnea hypopnea index, AHI≥15events/h) and severe SA (AHI≥30events/h) by PSG were diagnosed in 65% and 41% of patients. The mean AHI-PSG and RDI-PM were 30.4±22.6 and 21.7±14.2events/h, respectively. There was a significant positive correlation between AHI-PSG and RDI-PM (r=0.543; p=0.001). The correlation was stronger in the severe SA group (r=0.664; p=0.010), in a group whose apnea index was higher than hypopnea index (r=0.822; p=0.002), and in a group whose central sleep apnea (CSA) index was higher than obstructive sleep apnea index (r=0.977; p<0.001). RDI-PM cut-off value for identifying severe SA was 22 (area under the curve, 0.682; sensitivity, 64%; specificity, 75%). CONCLUSIONS: The pacemaker-based algorithm is a useful screening tool for SA in Japanese individuals, especially in the severe SA group, apnea-dominant group, and CSA-dominant group.

Right-sided cardiac resynchronization therapy with defibrillator implantation in a patient with corrected transposition of great arteries and persistent left superior vena cava.

Patients with corrected transposition of great arteries (c-TGA) are generally known to develop atrioventricular block, systemic right ventricular dysfunction, and tricuspid regurgitation over time, which are associated with tachyarrhythmia and progressive heart failure. A 76-year-old man had been diagnosed with c-TGA. He developed a cardiopulmonary arrest while playing tennis, and an automated external defibrillator detected ventricular fibrillation (VF). Immediate cardiopulmonary resuscitation and intensive treatment were performed. He fully recovered without neurological sequelae. QRS duration was 172 ms. Echocardiography showed marked dysfunction and dyssynchrony of the systemic right ventricle (systemic right ventricular end-diastolic diameter/end-systolic diameter = 73/60 mm, systemic right ventricular ejection fraction = 34%). For secondary prevention and treatment of progressive heart failure, cardiac resynchronization therapy with defibrillator (CRT-D) implantation was recommended. Venography via the left cubital superficial vein revealed a persistent left superior vena cava (PLSVC) and giant coronary sinus that did not connect with the right superior vena cava (SVC). Because of the acute angle between the PLSVC and great cardiac vein, we selected a right-sided approach via the right SVC. We were finally able to deliver a coronary sinus lead to the lateral vein. CRT-D implantation can be achieved even in patients with c-TGA and PLSVC. .

Significance of change in serum bilirubin in predicting left ventricular reverse remodeling and outcomes in heart failure patients with cardiac resynchronization therapy.

BACKGROUND: Research on the correlation of serum bilirubin level with cardiac function as well as outcomes in heart failure patients with cardiac resynchronization therapy (CRT) has not yet been reported. The aim of this study was to analyze the relationship between change in serum bilirubin level and left ventricular reverse remodeling, and also to clarify the impact of bilirubin change on clinical outcomes in CRT patients. METHODS: We evaluated 105 consecutive patients who underwent CRT. Patients who had no serum total-bilirubin data at both baseline and 3-9 months' follow-up or had died less than 3 months after CRT implantation were excluded. Accordingly, a total of 69 patients were included in the present analysis. The patients were divided into two groups: decreased bilirubin group (serum total-bilirubin level at follow-up≤that at baseline; n=48) and increased bilirubin group (serum total-bilirubin level at follow-up>that at baseline; n=21). RESULTS: Mean follow-up period was 39.3 months. In the decreased bilirubin group, mean left ventricular end-systolic diameter decreased from 54.5mm to 50.2mm (p=0.001) and mean left ventricular ejection fraction increased significantly from 29.8% to 37.0% (p=0.001). In the increased bilirubin group, there was no significant change in echocardiographic parameters from baseline to follow-up. In Kaplan-Meyer analysis, cardiac mortality combined with heart failure hospitalization in the increased bilirubin group was significantly higher than that in the decreased bilirubin group (log-rank p=0.018). Multivariate Cox regression analysis revealed that increased bilirubin was an independent predictor of cardiac mortality combined with heart failure hospitalization (OR=2.66, p=0.023). CONCLUSIONS: The change in serum bilirubin is useful for assessment of left ventricular reverse remodeling and prediction of outcomes in heart failure patients with CRT.

Shock Lead Dislodgement Related To Its Small Hair-Pin Curve In A Pocket -A Case Of Ratchet Syndrome.

There have been few reports about ratchet syndrome. We report a case of ratchet syndrome caused by small hair-pin curve of lead that triggered the lead retract itself. A 69-year-old man with a past history of inferior wall myocardial infarction, presented with progressive congestive heart failure. He underwent implantation of cardiac resynchronization therapy with an implantable cardiac defibrillator (CRTD) at our hospital. At 33 days after implantation, shock lead dislodgement was revealed. X-ray showed that the lead tip was in left subclavian vein, leaving its screw out, and a large part of the proximal portion of the lead was retracted into the pocket, while the other two leads remained in appropriate positions and the device had not rotated. An X-ray series showed that a hair-pin curve had been expanding gradually from just after implantation. In this case, relatively stiff shock lead was markedly bent and expanded the curve in the pocket, and ratchet-like movement occurred. We here report a new type of ratchet syndrome.