CVIT expert consensus document on primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) update 2022.

Primary Percutaneous Coronary Intervention (PCI) has significantly contributed to reducing the mortality of patients with ST-segment elevation myocardial infarction (STEMI) even in cardiogenic shock and is now the standard of care in most of Japanese institutions. The Task Force on Primary PCI of the Japanese Association of Cardiovascular Interventional and Therapeutics (CVIT) society proposed an expert consensus document for the management of acute myocardial infarction (AMI) focusing on procedural aspects of primary PCI in 2018. Updated guidelines for the management of AMI were published by the European Society of Cardiology (ESC) in 2017 and 2020. Major changes in the guidelines for STEMI patients included: (1) radial access and drug-eluting stents (DES) over bare-metal stents (BMS) were recommended as a Class I indication, (2) complete revascularization before hospital discharge (either immediate or staged) is now considered as Class IIa recommendation. In 2020, updated guidelines for Non-ST-Elevation Myocardial Infarction (NSTEMI) patients, the followings were changed: (1) an early invasive strategy within 24 h is recommended in patients with NSTEMI as a Class I indication, (2) complete revascularization in NSTEMI patients without cardiogenic shock is considered as Class IIa recommendation, and (3) in patients with atrial fibrillation following a short period of triple antithrombotic therapy, dual antithrombotic therapy (e.g., DOAC and single oral antiplatelet agent preferably clopidogrel) is recommended, with discontinuation of the antiplatelet agent after 6 to 12 months. Furthermore, an aspirin-free strategy after PCI has been investigated in several trials those have started to show the safety and efficacy. The Task Force on Primary PCI of the CVIT group has now proposed the updated expert consensus document for the management of AMI focusing on procedural aspects of primary PCI in 2022 version.

Role of intra-ventricular vortex in left ventricular ejection elucidated by echo-dynamography.

PURPOSE: From the correlation between the blood flow dynamics and wall dynamics in the left ventriocle (LV) analyzed using echo-dynamography, the ejection mechanisms and role of the intra-ventricular vortex in the LV were elucidated in detail during the pre-ejection transitional period (pre-ETP), the very short period preceding LV ejection. METHODS: The study included 10 healthy volunteers. Flow structure was analyzed using echo-dynamography, and LV wall dynamics were measured using both high-frame-rate two-dimensional echocardiography and a phase difference tracking method we developed. RESULTS: A large accelerated vortex occurred at the central basal area of the LV during this period. The main flow axis velocity line of the LV showed a linearly increasing pattern. The slope of the velocity pattern reflected the deformity of the flow route induced by LV contraction during the pre-ETP. The centrifugal force of the vortex at its junction with the main outflow created a stepwise increase of about 50% of the ejection velocity. CONCLUSION: Ejection of blood from the LV was accomplished by the extruding action of the ventricular wall and the centrifugal force of the accelerated vortex during this period. During ejection, acceralated outflow was considered to create a spiral flow in the aorta with help from the spherical structure of the Valsalva sinus.

The effectiveness of additional lead-shielding drape and low pulse rate fluoroscopy in protecting staff from scatter radiation during cardiac resynchronization therapy (CRT).

PURPOSE: Cardiac resynchronization therapy (CRT) often requires a long fluoroscopic time and protection from scatter radiation. This study reports on scatter radiation levels during CRT, with and without additional shielding, and using standard or low pulse rate fluoroscopy. MATERIALS AND METHODS: Additional lead-shielding drape (0.35-mm lead equivalent) was used on the left side of the table and pulsed fluoroscopy was performed at rates of 10 pulses/s (usual rate) and 7.5 pulses/s (low pulse rate). Fluoroscopy scatter radiation was measured for both pulse rates using an acrylic phantom with a radiation survey meter, both with and without the additional lead-shielding drape. RESULTS: With the additional lead-shielding drape, the fluoroscopy scatter radiation was reduced by 74.3% at 10 pulses/s and 78.6% at 7.5 pulses/s. If the fluoroscopy was changed from 10 pulses/s to 7.5 pulses/s, the scattered radiation at the primary physician's position was reduced by 24.0%. The combined use of additional shielding drape and low pulse rate fluoroscopy reduced scatter radiation by over 80%. CONCLUSION: Additional lead-shielding drape and low pulse rate fluoroscopy are effective in reducing the scattered radiation dose to physicians and nurses during CRT.

CVIT expert consensus document on primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) in 2018.

While primary percutaneous coronary intervention (PCI) has significantly contributed to improve the mortality in patients with ST segment elevation myocardial infarction even in cardiogenic shock, primary PCI is a standard of care in most of Japanese institutions. Whereas there are high numbers of available facilities providing primary PCI in Japan, there are no clear guidelines focusing on procedural aspect of the standardized care. Whilst updated guidelines for the management of acute myocardial infarction were recently published by European Society of Cardiology, the following major changes are indicated; (1) radial access and drug-eluting stent over bare metal stent were recommended as Class I indication, and (2) complete revascularization before hospital discharge (either immediate or staged) is now considered as Class IIa recommendation. Although the primary PCI is consistently recommended in recent and previous guidelines, the device lag from Europe, the frequent usage of coronary imaging modalities in Japan, and the difference in available medical therapy or mechanical support may prevent direct application of European guidelines to Japanese population. The Task Force on Primary Percutaneous Coronary Intervention of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) has now proposed the expert consensus document for the management of acute myocardial infarction focusing on procedural aspect of primary PCI.

Deformability of the pulsating left ventricular wall: A new aspect elucidated by high resolution ultrasonic methods.

BACKGROUND: Although the deformability of the left ventricular (LV) wall appears to be important in maintaining effective cardiac performance, this has not been debated by anyone, probably owing to the difficulties of the investigation. OBJECTIVES: This study applies a new technology to demonstrate how the LV wall deforms so as to adjust for optimum cardiac performance. SUBJECTS AND METHODS: Ten healthy volunteers were the subjects. Using echo-dynamography, an analysis at the "microscopic" (muscle fiber) level was done by measuring the myocardial axial strain rate (aSR), while the "macroscopic" (muscle layer) level contraction-relaxation/extension (C-R/E) properties of the LV wall were analyzed using high frame rate 2D echocardiography. RESULTS: Deformability of the LV was classified into three types depending on the non-uniformity of both the C-R/E properties and the aSR distribution. "Basic" deformation (macroscopic): The apical posterior wall (PW) thickness change was concentric and monophasic, whereas it was eccentric and biphasic in the basal part. This deformation was large in the PW, but small in the interventricular septum (IVS). The elongation of the mitral ring diameter and the downward movement of its posterior part were shown to be concomitant with the anterior extrusion of the PW. "Combined" deformation (macroscopic and microscopic): This was observed when the basic deformation was coupled with the spatial aSR distribution. Three patterns were observed: (a) peristaltic; (b) bellows-like; and (c) pouch-like. "Integrated" deformation: This was the time serial aSR distribution coupled with the combined deformation, illustrating the rotary pump-like function. The deformability of the LV assigned to the apical part the control of pressure and to the basal part, flow volume. The IVS and the PW exhibited independent behavior. CONCLUSIONS: The non-uniformity of both the aSR distribution and the macroscopic C-R/E property were the basic determinants of LV deformation. The apical and basal deformability was shared in LV mechanical function.

Need for radiation safety education for interventional cardiology staff, especially nurses.

OBJECTIVE: Cardiac interventional radiology (IR) can cause radiation injury to the staff who administer it as well as to patients. Although education in the basic principles of radiation is required for nurses, their level of radiation safety knowledge is not known. The present study used a questionnaire protocol to assess the level of radiation safety knowledge among hospital nurses. METHODS AND RESULTS: A questionnaire to assess the level of training and current understanding of radiation safety was administered to 305 nurses in 2008 and again to 359 nurses in 2010. Our study indicates that nurses had insufficient knowledge about radiation safety, and that a high percentage of nurses were concerned about the health hazards of radiation. Moreover, more than 80% of the nurses expressed an interest in attending periodic radiation safety seminars. Annual radiation protection training for hospital staff (including nurses) is important. CONCLUSIONS: Our results suggest that nurses do not have sufficient knowledge of radiation safety and should receive appropriate radiation safety training. Many had a minimal understanding of radiation and thus had significant concerns about the safety of working with radiation. Periodic radiation safety education/training for nurses is essential.

Non-uniform distribution of the contraction/extension (C-E) in the left ventricular myocardium related to the myocardial function.

OBJECTIVE: We attempted to disclose the microscopic characteristics of the non-uniform distribution of the contraction and extension (C-E) of the left ventricular (LV) myocardium using a new methodology (echo-dynamography). METHODS: The distributions of the "axial strain rate" (aSR) and the intra-mural velocity in the local areas of the free wall including the posterior wall (PW) and interventricular septum (IVS) were microscopically obtained using echo-dynamography with a high accuracy of 821 µm in the spatial resolution. The results were shown by the color M-mode echocardiogram or curvilinear graph. Subjects were 10 presumably normal volunteers. RESULTS: (1) Both the C-E in the pulsating LV wall showed non-uniformity spatially and time-sequentially. (2) The C-E property was better evaluated by the aSR distribution method rather than the intra-mural velocity distribution method. (3) Two types of non-uniformity of the aSR distribution were observed: i.e. (i) the difference of its (+)SR (contraction: C) or (−)SR (extension: E) was solely the "magnitude"; (ii) the coexistence of both the (+) SR and (−)SR at the same time. (4) The aSR distribution during systole was either "spotted," or "multi-layered," or "toned" distribution, whereas "stratified," "toned," or "alternating" distributions were observed during diastole. (5) The aSR distribution in the longitudinal section plane was varied in the individual areas of the wall even during the same timing. (6) To the mechanical function of the LV, there was a different behavior between the IVS and PW. . CONCLUSIONS: The aSR and its distribution were the major determinants of the C-E property of the LV myocardium. Spatial as well as time-sequential uniformity of either contraction or extension did not exist. The myocardial function changed depending on the assemblage of the aSR distribution, and by the synergistic effect of (+)SR and (-)SR, the non-uniformity itself potentially served to hold the smooth LV mechanical function.

New concept of the contraction-extension property of the left ventricular myocardium.

OBJECTIVES: Using newly developed ultrasonic technology, we attempted to disclose the characteristics of the left ventricular (LV) contraction-extension (C-E) property, which has an important relationship to LV function. METHODS: Strain rate (SR) distribution within the posterior wall and interventricular septum was microscopically measured with a high accuracy of 821µm in spatial resolution by using the phase difference tracking method. The subjects were 10 healthy men (aged 30-50 years). RESULTS: The time course of the SR distribution disclosed the characteristic C-E property, i.e. the contraction started from the apex and propagated toward the base on one hand, and from the epicardial side toward the endocardial side on the other hand. Therefore, the contraction of one area and the extension of another area simultaneously appeared through nearly the whole cardiac cycle, with the contracting part positively extending the latter part and vice versa. The time course of these propagations gave rise to the peristalsis and the bellows action of the LV wall, and both contributed to effective LV function. The LV contraction started coinciding in time with the P wave of the electrocardiogram, and the cardiac cycle was composed of 4 phases, including 2 types of transitional phase, as well as the ejection phase and slow filling phase. The sum of the measurement time duration of either the contraction or the extension process occupied nearly equal duration in normal conditions. CONCLUSION: The newly developed ultrasonic technology revealed that the SR distribution was important in evaluating the C-E property of the LV myocardium. The harmonious succession of the 4 cardiac phases newly identified seemed to be helpful in understanding the mechanism to keep long-lasting pump function of the LV.

Effect of the Great East Japan Earthquake on cardiovascular diseases--report from the 10 hospitals in the disaster area.

BACKGROUND: We reported an increased occurrence of cardiovascular diseases (CVDs) after the Great East Japan Earthquake by examining ambulance records, but it had to be confirmed by cardiologists. METHODS AND RESULTS: We enrolled patients admitted to the cardiology department of the 10 hospitals in the disaster area from 4 weeks prior to 15 weeks after March 11 in the years 2008-2011 (n=14,078). The weekly occurrence of several CVDs, including heart failure (HF), pulmonary thromboembolism (PTE) and infectious endocarditis (IE), was sharply and significantly increased after the Earthquake. CONCLUSIONS: The Disaster caused significantly increases in the occurrence of HF, PTE and IE.

[Importance of radiation education for nurses].

Radiation safety education/training is essential and is associated with a reduction in the radiation dose to both patients and staff. We used a questionnaire to assess the level of radiation safety knowledge among nurses working at Tohoku Kosei-Nenkin Hospital. Some nurses were also interviewed. The results of our study indicate that the nurses had insufficient radiation safety knowledge and that a high percentage of nurses were concerned about the health hazards of radiation. Moreover, more than 80% of the nurses expressed an interest in attending periodic radiation safety seminars. Appropriate radiation safety training is required to reduce nurse radiation doses, and an understanding of radiation safety can help to optimize the patient dose.

Physiological basis and clinical significance of left ventricular suction studied using echo-dynamography.

BACKGROUND: The existence as well as the exact genesis of left ventricular suction during rapid filling phase have been controversial. In the present study, we aimed at resolution of this problem using noninvasive and sophisticated ultrasonic methods. The clinical meaning was also documented. METHODS: Ten healthy male volunteers were examined by 2D echocardiography and echo-dynamography which enables us to obtain detailed instantaneous data of blood flow and wall motion simultaneously from the wide range of the left ventricle. The correlation of blood flow and wall motion was also studied. RESULTS: Rapid ventricular filling was divided into 2 phases which had different physiology. The early half (early rapid filling: ERF) showed the effect which was alike drawing a piston. This was proved by the shape of the velocity of inflow and the basal muscle contraction which actively assisted extension of the relaxed apical and central parts of the left ventricle, giving the negative pressure which causes the ventricular suction. The later half (late rapid filling: LRF) showed the turning of the fundamental flow and the squeezed basal part just like the sphincter in addition to the expansion of the apical and central portions of the left ventricle, and all of these cooperatively augmented the suction effect. CONCLUSION: Ventricular suction does exist to help ventricular filling. Simultaneous appearance of the contraction in the basal part and the relaxation or extension in the apical part during the post-ejection transitional period was made to occur the suction in the LV. And it can be said that the suction appeared in the late stage of systole as the one of the serial systolic phenomena.

A mobile communications system for home-visit medical services: the Electronic Doctor's Bag.

In the present study, "Electronic Doctor's Bag" which is a tele-healthcare tool for home-visit medical service using the mobile communications environment has been proposed and evaluated by preliminary experiments. It was shown that its basic function was sufficiently evaluated by a few doctors and nurses but further improvement in portability and operability is required on the basis of much more opinions of medical and nursing professionals.

A prospective multicenter registry of 0.010-inch guidewire and compatible system for chronic total occlusion: the PIKACHU registry.

OBJECTIVES: The aim of this study was to evaluate the safety and effectiveness of a 0.010-inch guidewire and a balloon catheter for treatment of chronic total occlusion (CTO). BACKGROUND: Pathological studies have shown that 60-70% of CTO lesions have microchannels of sizes equal to or less than 0.010 inch. METHODS: The PIKACHU registry is a prospective, multicenter registry study. A 0.010-inch guidewire had to be used as the first guidewire to attempt to pass the CTO lesion. The primary endpoint was device success using a 0.010 system. RESULTS: A total of 141 patients with 141 lesions were enrolled. The median duration of occlusion was 9 months (range 3-156). Average guiding catheter size was 5.8 +/- 0.7 Fr. and TRI was 76.6 %. CTOs were mostly between 10-20 mm long, observed in 53 occlusions. There were 107 lesions (75.9%) with bending of more than 45 degrees. Calcification was seen in 91 lesions (64.5%). A 0.010-inch guidewire was successfully passed through in 97 of 141 lesions (68.8%). A 0.010-inch guidewire compatible balloon catheter was passed in 87 of the 97 lesions (88.7%) and final PCI success was achieved in all the cases. The overall clinical success rate was 87.9% (124/141). No MACE or bleeding complications were observed. CONCLUSION: The PIKACHU registry data suggest that the 0.010-inch system is safe and practicable for treatment of CTO lesions.

Spiral systolic blood flow in the ascending aorta and aortic arch analyzed by echo-dynamography.

Using echo-dynamography, systolic blood flow structure in the ascending aorta and aortic arch was investigated in 10 healthy volunteers. The blood flow structure was analyzed based on the two-dimensional (2D) and 1D velocity vector distributions, changing acceleration of flow direction (CAFD), vorticity distribution, and Doppler pressure distribution. To justify the results obtained in humans, in vitro experiments were done using straight and curved tube models of 20mm diameter. The distribution of the CAFD showed a spiral staircase pattern along the flow axis line. In addition, the changes in the velocity profile in the short-axis direction, 2D distribution of the vorticity, and velocity vector distribution on the aortic cross-section plane, all confirmed the presence of systolic twisted spiral flow rotating clockwise toward the peripheral part of the ascending aorta. The rotation cycle of this spiral flow correlated inversely with the maximum velocity of the aortic flow, so that this cycle was shorter in early systole and longer in late systole. The model experiments showed similar results. The spiral flow seemed to be produced by several factors: (i) anterior shift of the direction of ejected blood flow due to the anterior displacement of the projection of the aorta; (ii) accelerated high pressure flow ejected antero-upward; (iii) inertia resistance at the peripheral boundary of the sinus of Valsalva; and (iv) reflection caused by the concave spherical structure of the inner surface of the basal part of the aorta. Because the main spiral flow axis line nearly coincided with the center line of the aorta, it is concluded that the occurrence of the spiral flow plays an important role in maintaining the blood flow direction passing through the cylindrical curved aortic arch and thus in keeping the most effective ejection as well as in dispersing the shear stress in the aortic wall.

A new 0.010-inch guidewire and compatible balloon catheter system: the IKATEN registry.

OBJECTIVE: To evaluate the safety and feasibility of a new 0.010-inch guidewire and a specialized balloon catheter for the 0.010-inch guidewire in routine percutaneous coronary intervention (PCI). BACKGROUND: Several reports have shown that a new 0.010-inch system is effective for specific situations where reduction of catheter size may be necessary. However, the safety of this system in routine PCI is unknown. METHODS: The IKATEN registry is a prospective, multicenter, nonrandomized registry study. Patients who underwent elective PCI with a 0.010-inch guidewire and its associated balloon catheter as primary devices were enrolled. The coprimary endpoints were clinical success and device success rates. The secondary endpoints were major adverse cardiac events (MACE) and bleeding complications. RESULTS: A total of 133 patients with 148 lesions were enrolled. The majority were male (75.3%), and mean age was 68 +/- 10 years. Type B2/C lesions comprised 60% of the lesions, prevalence of chronic total occlusion (CTO) was 16.9%, and bifurcation lesions were found in 22.3% of patients. A transradial approach was used in 79.7% of patients, and the average guiding catheter size was 5.1 +/- 0.4 Fr. Clinical success rate was 99.2%, and device success rate was 99.3%. Device failure occurred only in one case of chronic total occlusion because of unsuccessful guidewire passage. No MACE or bleeding complications were reported except for a small hematoma at the puncture site in one patient. Stent delivery success rate on 0.010-inch guidewire was 93.9% because of failure of stent balloon to pass eight lesions. CONCLUSION: The IKATEN registry data suggest that the 0.010-inch system is safe and its use is feasible in routine PCI including bifurcation and CTO lesions.

Blood flow structure and dynamics, and ejection mechanism in the left ventricle: analysis using echo-dynamography.

Using our "echo-dynamography", blood flow structure and flow dynamics during ventricular systole were investigated in 10 normal volunteers. The velocity vector distribution demonstrated blood flow during ejection was laminar along the ventricular septum. The characteristic flow structure was observed in each cardiac phases, early, mid- and late systole and was generated depending on the wall dynamic events such as peristaltic squeezing, hinge-like movement of the mitral ring plane, bellows action of the ventricle and dimensional changes in the funnel shape of the basal part of the ventricle, which were disclosed macroscopically by using the new technology of high speed scanning echo-tomography and microscopically by the strain rate distribution measured by phase tracking method. The pump function was reflected on the changes in the flow structure represented by the flow axis line distribution and the acceleration along the flow axis line. The acceleration of the ejection had three modes, "A", "B" and "C", and generated by the wall dynamic events. "A" appeared from the apical to the outflow area along the main flow axis line, "B" along the anterior mitral leaflet and the branched flow axis line, and "C" generated by the high speed vortex behind the mitral valve. The magnitude of the acceleration was estimated quantitatively from the velocity gradient along the flow axis line. Macroscopic and microscopic asynchrony in the myocardial contraction and extension appeared systematically in the local part of the ventricular wall, which was helpful for making the flow structure and for performing the smooth pump function.

[A case of cardiac angiosarcoma successfully treated with docetaxel].

We report a case of angiosarcoma of the right atrium presenting superior vena cava syndrome. The patient was a 61-year-old man. Echocardiography, CT and MRI revealed a tumor arising in the anterior wall of the right atrium. The tumor was hen-egg sized and unresectable because of the invasion of the pericardium, the right ventricular wall and the superior vena cava. An open biopsy and left brachiocephalic vein-right atrium bypass grafting were performed. The pathological diagnosis was angiosarcoma. The patient agreed to chemotherapy with docetaxel, which is known to be often effective against angiosarcoma of the scalp or face. After 5 courses of docetaxel administration (30 mg/m2 on day 1, 8 and 15 followed by 14 days. rest as one course), echocardiography and CT showed a remarkable tumor reduction, which was evaluated as a partial response. The chemotherapy was suspended for 8 months because of neutropenia and general fatigue as side effects of docetaxel. The administration of docetaxel was resumed and 4 courses were performed. The tumor, however, became resistant to docetaxel and formed metastatic involvements in the liver. Following treatments with paclitaxel, IL-2 and CPT-11 were ineffective for the primary tumor and liver metastases. He died of cardiac tamponade caused by massive hemorrhage into the pericardiac space from the tumor surface. He had long-term survival 31 months after the diagnosis. An effective treatment for cardiac angiosarcoma has not yet been established. Chemotherapy with docetaxel should be considered in the treatment of patients with cardiac angiosarcoma.

Evaluation of additional lead shielding in protecting the physician from radiation during cardiac interventional procedures.

Since cardiac interventional procedures deliver high doses of radiation to the physician, radiation protection for the physician in cardiac catheterization laboratories is very important. One of the most important means of protecting the physician from scatter radiation is to use additional lead shielding devices, such as tableside lead drapes and ceiling-mounted lead acrylic protection. During cardiac interventional procedures (cardiac IVR), however, it is not clear how much lead shielding reduces the physician dose. This study compared the physician dose [effective dose equivalent (EDE) and dose equivalent (DE)] with and without additional shielding during cardiac IVR. Fluoroscopy scatter radiation was measured using a human phantom, with an ionization chamber survey meter, with and without additional shielding. With the additional shielding, fluoroscopy scatter radiation measured with the human phantom was reduced by up to 98%, as compared with that without. The mean EDE (whole body, mean+/-SD) dose to the operator, determined using a Luxel badge, was 2.55+/-1.65 and 4.65+/-1.21 mSv/year with and without the additional shielding, respectively (p=0.086). Similarly, the mean DE (lens of the eye) to the operator was 15.0+/-9.3 and 25.73+/-5.28 mSv/year, respectively (p=0.092). In conclusion, although tableside drapes and lead acrylic shields suspended from the ceiling provided extra protection to the physician during cardiac IVR, the reduction in the estimated physician dose (EDE and DE) during cardiac catheterization with additional shielding was lower than we expected. Therefore, there is a need to develop more ergonomically useful protection devices for cardiac IVR.

Surgical management of localized left ventricular aneurysm associated with acute myocarditis.

We present a case of a localized left ventricular (LV) aneurysm in a 72-year-old woman with sudden onset of severe chest pain. A left ventriculogram revealed a small saccular outpouching protruding from the apex accompanied with narrow neck connection to the ventricular cavity. Both coronary arteries and global function were normal. We preoperatively diagnosed her as having an impending rupture in the congenital LV diverticulum because no inflammatory myocardial disease was suggested by general laboratory tests. After successful surgical treatment, microscopic examination for the myocardial specimens was performed and revealed diffuse lymphocytic infiltration associated with focal necrosis of myocardium. Histological findings were consistent with those of acute lymphocytic myocarditis. Without histological confirmation, an aneurysm caused by silent myocarditis might be misdiagnosed as a diverticulum.