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Pericardiocentesis under echocardiography guidance is a common procedure, but still poses a risk of injury to surrounding tissues. Nowadays, pericardiocentesis is being performed in patients with normal pericardium, for epicardial ablation or atrial appendage exclusion. Access to the normal pericardial space with the conventional needle procedure is very difficult. Thus, development of a novel method enabling safer pericardiocentesis is necessary. The present study aimed to assess the feasibility of using an originally developed ultrathin endoscopy-guided pericardiocentesis device in a swine model.We developed a novel ultrathin endoscopy-guided pericardiocentesis device. The device comprised a 1.2 mm ultrathin endoscope, a 20 G needle, and a grasping forceps. Pericardiocentesis was conducted as follows. A 12 Fr introducer sheath was inserted between the pericardium and the diaphragm under fluoroscopy. The pericardium was grasped with the originally developed forceps under endoscopy guidance to create a space in the pericardial sac. The 20 G needle was then inserted and a coiled-tip guidewire was placed into the pericardial sac. Five independent operators performed pericardiocentesis twice using this technique in a healthy pig with a body weight of approximately 25 kg. Procedural success rate and procedure time were assessed as the primary endpoints. The procedural success rate was 100% in all operators. The average procedure time was 65 ± 40 seconds (median, 46 seconds; interquartile range, 40-85 seconds). No procedure-related complications were noted.The study results indicate that ultrathin endoscopy-guided pericardiocentesis for normal pericardial space is feasible and safe.

Percutaneous coronary intervention (PCI) for anomalous coronary arteries is often difficult because the support provided by the guide catheter is insufficient. We encountered a patient with severe three-vessel coronary disease including a totally occluded anomalous right coronary artery (RCA) originating from the left sinus of Valsalva. Initial PCI for the anomalous RCA via the transradial approach failed. Therefore, we constructed a three-dimensional (3D) aortocoronary model and conducted an in vitro simulation to plan the second PCI and found that a Judkins left (JL) 3.5 guide catheter in the power position yielded maximum backup support for the anomalous RCA. Thus, the second PCI was conducted using an 8 Fr JL 3.5 guide catheter in the power position via the transfemoral approach. The procedure was smooth and successful, without any adverse events. Our experience suggests that case-specific 3D models are useful for strategic planning of complex PCIs.

Myocardial fractional flow reserve (FFR) is a reliable index in coronary intervention. A simple FFR measurement does not predict the true functional severity of an individual stenosis in multiple sequential coronary stenoses because of complex interaction between the stenoses. Application of the theoretical equations to predict the true FFR of individual stenosis is limited in a tandem lesion. Two novel equations applicable to a multiple sequential coronary stenoses are mathematically derived. One predicts the true FFR of each stenosis (equation A), and the other predicts the true FFR after releasing a given stenosis (equation B). The present study aimed to validate the two derived equations in an in vitro model of coronary circulation.Predictive FFR was compared with true FFR in an in vitro model of three sequential stenoses using linear regression analysis. The difference between apparent FFR and true FFR was compared with the difference between predictive FFR and true FFR. The legitimacy of equation A was first assessed. A close correlation was found between predictive FFR and true FFR (r² = 0.92). The difference between predictive FFR and true FFR was significantly lower compared to the difference between apparent FFR and true FFR (0.18 ± 0.10 vs 0.05 ± 0.05; P.001). The legitimacy of equation B was also assessed, and a close correlation was found (r² = 0.97). The difference was significantly lower when we applied equation B (0.13 ± 0.06 vs 0.04 ± 0.02; P.001).Equations A and B strongly predict the true value of FFR in the experimental model of coronary circulation.

Although several types of distal embolic protection devices have been developed, they are usually difficult to use because of their stiff and bulky characteristics. We present a novel method to deliver the coronary embolic protection filter via a manual thrombectomy catheter.We modified the Filtrap embolic protection filter (Nipro Corporation) to pass through the aspiration thrombectomy catheter. Three interventional cardiologists performed the Filtrap delivery with in vivo and in vitro coronary arteries using two different methods. The in vitro experiments were performed using a Circuit Cardiac Catheterization Simulator (Just Medical Corporation) with and without coronary artery stenosis. The in vivo experiment was performed using a normal pig coronary artery. The times required for Filtrap delivery in the two different methods were compared. The target lesions were the main and side branch of the left anterior descending, left circumflex, and right coronary arteries.The average Filtrap delivery time when using the thrombectomy catheter was significantly shorter compared to the time using the conventional method (in vitro experiment without coronary stenosis, 39 ± 14 seconds vs 30 ± 6 seconds and P=.019; in vitro experiment with multiple coronary stenosis, 69 ± 55 seconds vs 32 ± 11 seconds and P=.012; in vivo experiment, 169 ± 166 seconds vs 51 ± 12 seconds; P=.019).The study results indicate that delivery of the coronary embolic protection filter via a manual thrombectomy catheter may simplify the procedure and decrease the procedure time.

The objective of this study was to create a calcified total occlusion model in porcine coronary arteries using a catheter-based technique.Chronic total occlusion (CTO) represents 10-20% of all angioplasty cases and remains a challenge for interventional cardiologists. One of the limitations to successful recanalization is the failure to cross the wire through the CTOs.Twenty swine underwent total occlusion creations in the coronary arteries. Via a carotid artery, previously prepared bone chips with absorbable sponge were delivered into the coronary arteries using catheter-based techniques. Twenty-eight days post creation, coronary angiography and histology were performed.Twelve animals survived and 10/12 had successful total occlusions. There were successful total occlusions in 100% (8/8) of the left anterior descending coronary arteries in the animals that survived. Angiography showed visible calcified total occlusions under fluoroscopy and also showed bridge collaterals distal to the occlusions (4/8) or contralateral collaterals from the right coronary arteries (4/8). The histology showed calcified nodules and abundant microchannels within the occlusions, media, and adventitia.We could successfully create a reliable and repeatable porcine coronary model of calcified total occlusions. This method can be utilized in many preclinical evaluations of CTO technologies.