Comparison of laboratory detection methods of aspirin resistance in coronary artery disease patients.

Aspirin reduces the prevalence of nonfatal myocardial infarction, stroke, and death by 25.0% in high risk group of patients with cardiovascular disease. Previous studies have estimated that about 5.5-56.8% of the population are aspirin resistant. The mechanisms of aspirin resistance (AR) have not been fully understood. We compared the detection methods for AR using traditional platelet aggregometry and VerifyNow system. One hundred and seventy-two coronary artery disease patients who had taken aspirin only or combinations with aspirin and clopidogrel for over 7 days were included. Of the 55 patients with aspirin only, aggregometer detected six AR (10.9%) and VerifyNow identified 10 AR (18.2%) cases. Among 117 patients with combined therapy, none (0.0%) and 10 (8.5%) of AR were detected by aggregometer and VerifyNow, respectively. There were six (3.4%) patients of AR defined by both methods and they all received aspirin monotherapy. Although the correlation between the aggregometry and VerifyNow was low, with defined criteria both methods gave 91.9% agreement to find AR. VerifyNow showed a higher sensitivity to detect AR. Further studies are required to biologically define AR and to alter therapy based on platelet function tests.

Treatment of aortic stenosis with aortic valve bypass (apicoaortic conduit) surgery: an assessment using computational modeling.

BACKGROUND: Aortic valve bypass surgery treats aortic valve stenosis with a valve-containing conduit that connects the left ventricular apex to the descending thoracic aorta. After aortic valve bypass, blood is ejected from the left ventricle via both the native stenotic aortic valve and the conduit. We performed computational modeling to determine the effects of aortic valve bypass on aortic and cerebral blood flow, as well as the effect of conduit size on relative blood flow through the conduit and the native valve. METHODS: The interaction of blood flow with the vascular boundary was modeled using a hybrid Eurelian-Lagrangian formulation, where an unstructured Galerkin finite element method was coupled with an immersed boundary approach. RESULTS: Our model predicted native (stenotic) valve to conduit flow ratios of 45:55, 52:48, and 60:40 for conduits with diameters of 20, 16, and 10 mm, respectively. Mean gradients across the native aortic valve were calculated to be 12.5, 13.8, and 17.6 mm Hg, respectively. Post-aortic valve bypass cerebral blood flow was unchanged from preoperative aortic valve stenosis configurations and was constant across all conduit sizes. In all cases modeled, cerebral blood flow was completely supplied by blood ejected across the native aortic valve. CONCLUSIONS: An aortic valve bypass conduit as small as 10 mm results in excellent relief of left ventricular outflow tract obstruction in critical aortic valve stenosis. The presence of an aortic valve bypass conduit has no effect on cerebral blood flow. All blood flow to the brain occurs via antegrade flow across the native stenotic valve; this configuration may decrease the long-term risk of cerebral thromboembolism.

Chip- and board-level optical interconnections using rigid flexible optical electrical printed circuit boards.

A new optical interconnection scheme based on a rigid flexible optical electrical printed circuit board (RFOE-PCB) is suggested. The easily installed RFOE-PCB can be universally applied for both chip- and board-level optical interconnections. This letter describes the detailed fabrication process, optical properties, and heat-resisting property of the RFOE-PCB. The fabricated RFOE-PCB was also successfully demonstrated with a 2.5-Gb/s data transmission through a 45 degrees-ended optical waveguide embedded in the RFOE-PCB.

Nonselective left internal mammary artery angiography during right transradial coronary angiography: a simple, rapid, and safe technique.

Internal mammary artery angiography is increasingly required, but the technique for left internal mammary artery (LIMA) angiography during right transradial coronary angiography is not well established. The authors investigated the feasibility and safety of a new, simple, and rapid nonselective technique. Following right transradial coronary angiography, LIMA angiography was performed using a 5 French (Fr) Judkins JL-3.5 catheter in 110 patients. The catheter, placed in the ascending aorta with its natural curve, was withdrawn slowly while being rotated clockwise to engage its tip in the proximal left subclavian artery. Contrast material was injected while sphygmomanometer cuff inflation was applied to the left upper arm. In the last 50 patients, the angiography was performed twice randomly with and without the cuff inflation. In 108 patients (98%), the catheter was successfully engaged in the subclavian artery in a mean of 11 +/- 8 seconds (range, 3-136) from the time when it was withdrawn from the ascending aorta, and nonselective LIMA angiography was successfully performed. The image quality of the angiograms was satisfactory in 103 (95%) of the 108 patients. In the last 50 patients, the image quality of the angiograms was determined satisfactory in 48 (96%) and 45 (90%) patients, with and without the cuff inflation, respectively. The difference was statistically not significant. There were no complications, including arterial dissection and thromboembolism. In conclusion, nonselective LIMA angiography can be readily and safely performed during right transradial coronary angiography using a 5 Fr Judkins JL-3.5 catheter.

Bilateral selective internal mammary artery angiography via right radial approach: clinical experience with newly designed Yumiko catheter.

The radial artery has been increasingly used as a primary access site for coronary angiography and intervention. But the technique for internal mammary artery (IMA) visualization via the right radial artery has not been well described. Therefore, the study was conducted to investigate the feasibility, safety, and adequacy of selective bilateral IMA angiography via the right radial artery using the recently developed Yumiko catheter. From November 1999 to October 2000, both IMA angiographies were undertaken immediately following the diagnostic coronary angiogram taken from right transradial approach in 114 patients. IMA angiography was successfully obtained in 99% (113/114) patients. For left IMA angiography, 73 (64%), 28 (25%), and 12 (11%) imagings were obtained in a selective, a semiselective, and a nonselective way, respectively. After initial periods of 33 left-IMA-only imaging, right IMA angiography was obtained in 81 patients (phase 2). Selective right IMA imaging was done in 73 (90%), semiselective in 6, and nonselective in 2 patients. The reasons for failure of selective or semiselective visualization were severe vascular tortuosity, far distal anatomical origin of left IMA and ulcerative plaque, or acutely angled left subclavian artery. The feasibility and safety of selective and semiselective bilateral IMA angiography were demonstrated using a 5 Fr Yumiko catheter from the right radial approach. Cathet Cardiovasc Intervent 2001;54:19-24.

Combined right transradial coronary angiography and selective carotid angiography: safety and feasibility in unselected patients.

We evaluated the safety and feasibility of ad hoc carotid angiography following the right transradial coronary angiography. Selective carotid angiography was performed subsequent to coronary angiography in 213 consecutive patients. A 5 Fr Simmons catheter was reformed in descending or ascending aorta, then, withdrawn and rotated to cannulate the left and right carotid artery. Both carotid angiography was performed selectively in 211 (99%) patients. In two patients with severely tortuous subclavian artery, selective cannulation of the left carotid artery failed. There was no thromboembolism or arterial dissection. After the learning phase of 50 patients, the time to reform the catheter in aorta and to cannulate the left and right carotid artery was 50 +/- 77, 66 +/- 68, and 58 +/- 57 sec, respectively. Total procedural time was 195 +/- 145 sec. In conclusion, ad hoc carotid angiography can be performed reliably and safely following the right transradial coronary angiography. It might be useful for evaluation of an isolated or associated carotid artery stenosis. Cathet Cardiovasc Intervent 2001;53:380-385.

Retrieval of dislodged and disfigured transradially delivered coronary stent: report on a case using forcep and antegrade brachial sheath insertion.

We report a case of dislodged and damaged stent during transradial coronary procedure using 6 Fr device, which was successfully retrieved by using a forcep and 8 Fr antegrade brachial sheath. The disfigured and bulky stent can be removed, after their retrieval from the coronary circulation, using a forcep inserted through an 8 Fr brachial artery sheath if the radial artery is deemed too small to accommodate larger sheath.

Primary stenting for acute myocardial infarction via the transradial approach: a safe and useful alternative to the transfemoral approach.

BACKGROUND: Primary stenting in acute myocardial infarction (AMI) has been demonstrated to reduce recurrent ischemic events. However, transradial stenting in AMI has not been well established. Therefore, we sought to investigate the feasibility and utility of transradial coronary stenting in patients with AMI. METHODS: From April 1998 to April 1999, 56 patients (43 male; mean age of 57 years) who arrived within 6 hours of pain onset with culprit vessel size > 2.5 mm constituted this study. The transradial approach (Group 1) was used in 30 patients with hemodynamically stable and palpable right radial pulse. The transfemoral approach (Group 2) was used for vascular access in the remainder of patients (26) who might have required a second vascular access site for intraaortic balloon pumping (in cardiogenic shock) and/or a transvenous temporary pacemaker. RESULTS: Overall success rate was achieved in 54 of 56 patients (96%). The success rate was 90% (27/30) in Group 1 and 96% (25/26) in Group 2. The cannulation time (from patient arrival at the catheterization room to the time of arterial cannulation) and the total procedure time (from patient arrival at the catheterization room to the completion of the procedure) were not significantly different between Group 1 and Group 2 (9.2+/-5.3 versus 8.9+/-5. 8 minutes, p>0.05; 53.7+/-19.4 versus 57.5 +/-26.8 minutes, p>0.05, respectively). In the Group 1 patients, there was no forearm ischemia or loss of radial pulse during the 30-day follow-up period. CONCLUSION: Primary coronary stenting for acute myocardial infarction via the transradial approach is a safe and feasible alternative to the conventional transfemoral approach, and is especially useful for hemodynamically stable patients who do not require a second vascular access site.

Successful inoue balloon mitral commissurotomy in double-orifice mitral stenosis.

We report a rare case of stenotic double-orifice mitral valve of incomplete bridge type in a 40-year-old male. The fibrous bridge tissue between the leaflets was successfully split with a 24-mm Inoue balloon catheter using the stepwise dilation technique. Cathet. Cardiovasc. Intervent. 49:200-203, 2000.

Determination of free acetaldehyde in total blood for investigating the effect of aspartate on metabolism of alcohol in mice.

To explore the effect of sodium L-aspartate monohydrate (aspartate) as a NAD+ regenerating agent for acetaldehyde in alcohol metabolism, a simple HPLC method has been developed for the measurement of free acetaldehyde in total mice blood digested with alcohol and aspartate. The blood samples were collected in EDTA Vacutainer tubes, and treated with 2,4-dinitrophenylhydrazine (DNP hydrazine) reagent in total blood. Acetaldehyde DNP hydrazone was extracted from total blood and analyzed by HPLC using an Ultrasphere ODS column. The compounds were separated using acetonitrile-water (50:50, v/v) as mobile phase and detected at 356 nm. The detection limit for acetaldehyde DNP hydrazone was 0.1 ppm. A blank determination was carried out for each analysis and subtracted from the results. The amount of acetaldehyde in blood has been determined as a function of time lapse after sole alcohol administration and aspartate ingestion followed by alcohol administration, respectively. This comparative analysis demonstrates that the ingestion of aspartate before the administration of alcohol dramatically decreases the aldehyde level in blood, and aspartate may be utilized as a prospective antagonist for acceleration of ethanol metabolism and prevention of acetaldehyde toxicity.

Atrial fibrillation in patients with permanent VVI pacemakers: risk factors for atrial fibrillation.

OBJECTIVES: Atrial fibrillation (AF) does not only deteriorate the cardiac function and increases the thromboembolic risk but also triggers rapid and irregular ventricular rhythm in patients with atrial synchronous pacing. However, the risk factors for the development of AF in patients with pacemakers are not clearly determined yet. The present study was designed to determine the risk factors for AF in patients with VVI pacemakers. METHODS: This study included 80 patients (41 sick sinus syndrome, 39 AV block) who were followed for more than 6 months or developed AF regardless of the duration of follow-up after implantation of VVI pacemakers. Patients were divided into two groups according to whether or not AF developed during follow-up (mean: 25.7 +/- 2.5 months): group A developed AF and group B did not. The underlying arrhythmias, cardiovascular risk factors, left atrial size, characteristics of P wave were compared between the two groups. RESULTS: The mean age of the patients was 58.9 +/- 11.4 years and 28 (35%) were male. AF developed in 13 (16.3%) of 80 patients with VVI pacemakers. Sick sinus syndrome (SSS) as an underlying arrhythmia was significantly more frequent in group A than group B (84.6% vs. 44.8%, p < 0.01). P wave width was greater in group A (127.6 +/- 24.8 ms) than in group B (110.7 +/- 17 ms) (p < 0.05). There was, however, no significant difference in cardiovascular risk factors, left atrial size, P wave axis and amplitude between the two groups. CONCLUSION: These results suggest that sinus node dysfunction and intra-atrial conduction delay may be the risk factors for AF in patients with VVI pacemakers. Further studies are needed to determine how sick sinus syndrome and intra-atrial conduction delay increase the risk for AF in patients with VVI pacemakers.

Interrupted circular suture: bleeding control during cesarean delivery in placenta previa accreta.

Rapid accumulation of blood from the placental separation site during cesarean delivery for placenta previa obscures the surgical field and quickly leads to deterioration of the patient's vital signs. We used the following technique in eight cases of intractable bleeding among 49 cesareans for placenta previa. Following failure to control the bleeding by suture at the placental separation site via the lower segment cesarean incision, the vessels were ligated using interrupted 2-3-cm sutures at 1-cm intervals in a circle around the bleeding area on the serosal surface of the uterus. The sutures were placed as deeply as possible in order to reach the endometrium. This led to a marked decrease in bleeding and allowed the small vessels to be easily identified and ligated. The amount of blood transfused and the operation time were gradually reduced as we became adept in the use of this procedure. Our experience suggests that this technique could reduce the use of hysterectomy in cesarean for placenta previa.

Body stalk anomaly--a case report.

A case is presented of an amnionic rupture sequence which led to massive fetal ventral herniation and lordoscoliosis. Characteristic ultrasonographic findings of an omphalocele, fetal attachment to the placenta, and the absence of free-floating umbilical cord were observed.

An unusual venous anomaly of the placenta.

The authors present an unusual vascular anomaly of the placenta. The placenta was very large, weighing 1,490 g. On the fetal surface, numerous dilated and tortuous vessels were observed on and under the chorionic membrane, of which three branches arose from a vein that was connected to the umbilical vein. One of them had a 5 x 2.5 cm aneurysmal dilatation, where three secondary branches arose. These venous channels were dilated and tortuous. The longest secondary branch was 133 cm in length and 1.2 cm in mean diameter and led into the placenta. Multiple, severely coiled or straight small branches arising from these vessels were also observed as vascular tangles. Some of these smaller vessels also led into the placenta. All abnormal vessels were veins. The umbilical cord was also normal except for a membranous insertion, and the placenta was unremarkable except for its large size.

Window operation: an alternative treatment method for Bartholin gland cysts and abscesses.

Recently, we developed the "window operation" as a more effective way to treat Bartholin gland cysts and abscesses. The window operation was used to treat 25 Bartholin cysts and 22 Bartholin abscesses during a 3-year period from October 1, 1986 to September 30, 1989. Under local anesthesia, a small piece of skin including the cyst wall was excised in an oval shape, and suturing was performed along the excised margin. Postoperative antibiotics were given in cases of acute inflammation. A new mucocutaneous junction was observed at the 4-week postoperative checkup. No complications or recurrences have been observed during the study period. The window operation can be an alternative method of treatment for Bartholin gland cysts or abscesses.