[Mitral valve replacement after previous coronary artrey bypass grafting( CABG) with functioning left internal thoracic artery( LITA) grafts in an elderly patient; report of a case].

An 85-year-old woman had a history of coronary artery bypass grafting (CABG) performed 7 years ago, and dyspnea on effort had been worsening recently. Since echocardiography showed severe mitral valve regurgitation( MR), mitral valve repair was suggested. Preoperative enhanced computed tomography (CT) showed the patent functioning left internal thoracic artery (LITA) graft. Mitral valve replacement (MVR) using a 25 mm CEP bioprosthesis was performed successfully via resternotomy without any intraoperative injury of the heart. Myocardial protection without clamping of functioning LITA was done by both antegrade and retrograde continuous coronary perfusion (RCCP) under mild hypothermia. The postoperative clinical course was uneventful without any hemodynamic compromise. She was discharged on postoperative day 21 without any cardiac events following early introduction of cardiac rehabilitation. From these results, mitral valve reoperation by RCCP under mild hypothermia without control of functioning internal thoracic artery( ITA) grafts could be a safe option in some cases.

[Initial clinical experience of early cardiac rehabilitation for very elderly patients over 85 years old following open heart surgery].

In this study, we evaluated the initial clinical experience of early cardiac rehabilitation( CR) for very elderly patients over 85 years old after open heart surgery. From September 2007 to January 2011, 7 consecutive patients (85~90 years, mean 85.9 years, male:female=4:3) who underwent cardiac surgery in our institute were selected. Preoperative activity of daily living (ADL) scores were similar in all cases, and 1 patient used a cane for walking. Preoperative New York Heart Association (NYHA) classification was class III :3, class IV:4. Three patients were admitted for acute congestive heart failure approximately 1 month prior to surgery. Standard open heart surgery using bioprosthesis was performed: 3 patients underwent mitral valve replacement( MVR), 3 had aortic valve replacement( AVR), and 1 had tricuspid valve replacement (TVR). Postoperative clinical course was uneventful, and the mean time of ventilator support was 12.1 hours. Thereafter, early CR was introduced at the intensive care unit( ICU) in all patients, and the mean time of introduction of early rehabilitation was 1.7 days. In the last 4 cases, early CR was done the 1st day following surgery. CR was effectively performed in all cases without any problems or cardiac events, and all patients improved enough to leave their beds at 3~7 days, a mean of 4.4 days after surgery. The mean hospital stay after surgery was 30.9 days( 23 ~ 42 days), almost all patients were able to walk independently, and ADL scores at discharge were improved. Only 2 patients required a cane for walking. Postoperative NYHA classification was improved to class I :5, class II :2. From these results, early CR for very elderly patients over 85 years old could be a safe and effective tool to improve and maintain the ADL and quality of life following surgical intervention.

[Open heart surgery in a patient with a history of Takotsubo cardiomyopathy].

An 81-year-old man had a history of Takotsubo cardiomyopathy induced by general fatigue after travel and acute gastritis 2 years previously. Recently, dyspnea on effort had been worsening. Since preoperative echocardiography showed severe aortic valve regurgitation (AR) with left ventricular (LV) dilatation, aortic valve replacement (AVR) by the standard procedure was indicated. Since the safety of the perioperative clinical course including recurrence of Takotsubo syndrome and hemodynamic compromise was unclear, a thorough examination was performed before surgical intervention. AVR with a 21 mm Mosaic bioprosthesis was performed. Transesophageal echocardiography (TEE) during operation did not demonstrate any sign of Takotsubo syndrome and good LV function was maintained. The patient was discharged on postoperative day 18 without any cardiac events including arrhythmia or clinical symptoms such as chest pain. Based on these results, open heart surgery under cardiopulmonary bypass (CPB) and cardiac arrest could be safely performed in patients with a history of Takotsubo cardiomyopathy with minimum use of cardiac agents including cathecholamine and sufficient perioperative removal of emotional and physical stress.

Relationship between epicardial fat measured by 64-multidetector computed tomography and coronary artery disease.

BACKGROUND: Epicardial fat (EF) is the visceral fat of the heart deposited under the visceral layer of the pericardium and has the same origin as abdominal visceral fat, which is shown to be strongly related to the development of coronary artery disease (CAD). We measured the volume of EF (EFV) by 64-multidetector computed tomography (MDCT) and studied the relationship between EFV and the severity of CAD. HYPOTHESIS: Epicardial fat volume increases steeply in patients with significant coronary artery stenosis and in those with severe coronary artery calcification. METHODS: We studied 197 patients with suspected CAD who underwent 64-MDCT and coronary angiography. Cross-sectional tomographic cardiac slices (3.0 mm thick) from base to apex (30 to 40 slices per heart) were traced semiautomatically and EFV was measured by assigning Hounsfield units ranging from -30 to -250 to fat. RESULTS: Epicardial fat volume was 99.4 ± 40.0 ml (range, 11.6 to 263.8 mL) and coronary artery calcium score (CACS) was 267.2 ± 605.1 (range, 0 to 3780). There was a significant relationship between EFV and CACS (r=0.210, P=0.003). Patients with EFV >100 had a CACS that was significantly higher than in those with EFV <100 (384.0 ± 782.0 vs 174.8 ± 395.6; P = 0.016). The incidence of significant CAD was significantly higher in patients with EFV >100 compared with those with EFV <100 (40.2% vs 22.7%; P=0.008). The EFV was significantly higher in patients with severe coronary artery stenosis and in those with severe coronary artery calcification (CACS >400). CONCLUSIONS: Our results showed that EFV was associated with coronary atherosclerosis, and EFV increased steeply in patients with severe coronary artery stenosis and in those with severe coronary artery calcification.

Prevalence of subclinical atherosclerosis in asymptomatic patients with low-to-intermediate risk by 64-slice computed tomography.

BACKGROUND: Recent research has shown that cardiovascular risk scoring significantly underestimates or misclassifies risk in key subsets of the population. There is a growing need for a noninvasive imaging to detect a subclinical atherosclerosis. Thus we hypothesized that 64-slice computed tomography (CT) could effectively detect subclinical atherosclerosis in asymptomatic patients with low-to-intermediate risk. METHODS: Four hundred and fifteen asymptomatic patients with coronary risk factors underwent 64-slice CT. When 64-slice CT showed a significant stenosis we recommended that patients receive stress myocardial perfusion imaging (MPI). When MPI showed ischemic findings, we recommended that patients receive a coronary revascularization procedure. We followed our patients for a mean of 2.8 years (2.4-3.3 years). RESULTS: We detected coronary plaques in 295 patients (71.1%). Of 135 patients with a negative scan for coronary calcification, noncalcified plaques were detected in 15 patients (11.1%). Two hundred and thirty-five patients (79.7%) had multiple plaques and, on average, one patient had 4.6 plaques. Significant coronary stenosis was detected in 91 patients (21.9%) and 85 patients underwent stress MPI. Myocardial ischemia was found in 27 patients (31.8%) and 21 patients underwent percutaneous coronary intervention. For a mean follow-up period of 2.8 years, four patients developed acute coronary syndrome. CONCLUSION: Our results showed that the prevalence of subclinical atherosclerosis in asymptomatic patients with low-to-intermediate risk was very high and one-fifth of them had significant stenosis as shown by 64-slice CT. However, myocardial ischemia was detected in only one-third of them.

[Clinical experience with intravenous administration of nifekalant hydrochloride for ventricular tachycardia in a hemodialysis patient after open heart surgery].

A 78-year-old man with chronic renal failure (CRF) on hemodialysis (HD) was diagnosed as having severe aortic regurgitation with left ventricular dysfunction. Aortic valve replacement with a 21 mm ATS mechanical bileaflet prosthesis was performed without intraoperative complications. Sustained ventricular tachycardia suddenly occurred 1 day after surgery, then intravenous administration of nifekalant hydrochloride (NIF) was started at a dose of 0.40 mg/kg/hr. Life-threating ventricular arrhythmia was controlled, hemodynamic compromise was improved dramatically. NIF was regulated with a low-dose of 0.24 mg/kg/hr to prevent malignant side effect such as torsa de pointes. Since QTc was elongated to 0.57 seconds 11 hours after administration, NIF was stopped. Low-dose intravenous administration of NIF in patients with CRF on HD could be useful to prevent ventricular tachyarrhythmias without any adverse effect after cardiac surgery.

Prevalence of non-calcified coronary plaque on 64-slice computed tomography in asymptomatic patients with zero and low coronary artery calcium.

OBJECTIVES: To study the prevalence of noncalcified plaque in asymptomatic low-risk patients with no or mild coronary artery calcium (CAC). METHODS: From 502 patients with coronary risk factors who underwent 64-slice computed tomography, 224 asymptomatic patients were identified with no CAC (n=117) or mild CAC (n=107; defined as patients with Agatston scores from 1 to 100). RESULTS: Patients with no CAC were younger and had diabetes less often. Medications and laboratory data were not significantly different between the two groups. The prevalence of noncalcified plaque was 11.1% in patients with no CAC and 23.4% in the mild CAC group (P=0.0142). Multiple plaques were detected in 2.6% of the group with no CAC and 3.7% of the group with mild CAC (P=0.5934). Significant coronary artery stenosis was found in one patient in the group with no CAC (0.9%) and three patients in the group with mild CAC (2.8%, P=0.3506). CONCLUSIONS: Significant percentages of noncalcified plaque were found in asymptomatic low-risk patients with no or mild coronary calcium.

Distribution of coronary atherosclerosis in patients with coronary artery disease.

The distribution of coronary atherosclerosis has not been fully clarified. We measured coronary artery calcium score (CACS) in 624 consecutive patients for the right coronary artery (RCA), left main trunk (LMT), left anterior descending coronary artery (LAD), and left circumflex coronary artery (LCx), then calculated total CACS. Coronary artery calcium score was measured using the Agatston method. We divided these patients into four groups: CACS 1-100 (Group A, n = 267), CACS 101-400 (Group B, n = 160), CACS 401-1000 (Group C, n = 110), and CACS >1000 (Group D, n = 87). In Group A, B, and C, the CACS in LAD was significantly higher than in the other three arteries (P < 0.0001). In Group D, the CACS was not significantly different between LAD and RCA (P = 0.6930). In Groups A, B, and C, coronary artery calcium (CAC) was more frequently found in LAD compared with other arteries (P < 0.0001). However, in Group D the prevalence of CAC was not significantly different among the three arteries (P = 0.4435). Coronary artery calcium was found more frequently in LAD than in the other coronary arteries in patients with mild to high CAC, but not in those with very high CAC.

Prevention of coronary slow flow/no reflow during percutaneous coronary intervention by the use of embolic protection device, 'Filtrap'.

A 68 year-old man underwent percutaneous coronary intervention (PCI). A 64 multi-slice computed tomography (MSCT) demonstrated a non-calcified plaque with positive remodeling. Intravascular ultrasound showed severe attenuation which suggested high risk of coronary no reflow during PCI. In order to avoid this, we used an embolic protection device, Filtrap. Immediately after deployment of a Taxus stent, ST-elevation with chest pain and coronary no reflow appeared. After retrieval of the Filtrap device, ST-elevation and no reflow disappeared. The filter was filled with yellow materials. This case suggests two things: that 64 MSCT can detect coronary plaque with high-risk of coronary no reflow during PCI; and that using a Filtrap device can effectively prevent the coronary no reflow during PCI.

Prevalence of subclinical atherosclerosis in asymptomatic diabetic patients by 64-slice computed tomography.

OBJECTIVES: Patients with diabetes have a 2-fold to 4-fold higher risk of a cardiovascular event than nondiabetic patients. Thus there is a need to identify patients with diabetes who are at risk of cardiovascular events before the onset of symptoms. We studied the prevalence of coronary artery disease in asymptomatic diabetic patients compared with asymptomatic nondiabetic patients by 64-slice computed tomography (CT). METHODS: From 425 asymptomatic patients with coronary risk factors but without known coronary artery disease who underwent 64-slice CT, we identified 93 asymptomatic diabetic patients (diabetic group) and 93 age-matched and sex-matched asymptomatic nondiabetic patients. RESULTS: Clinical characteristics were not significantly different between the two groups. Total coronary calcium score was significantly higher in diabetic group than that in nondiabetic group (median 117 vs. 53.5, P<0.0001). No coronary calcium was detected in 30.0% of nondiabetic group compared with 15.1% of diabetic group (P=0.0022). Coronary calcium score more than 400 was detected in 9.7% of nondiabetic group compared with 36.6% of diabetic group (P<0.0001). Coronary plaques were found in 67.7% of nondiabetic group compared with 91.4% of diabetic group (P<0.0001). Multiple plaques were detected in 57.0 and 77.4% of patients in nondiabetic and diabetic group, respectively (P=0.0030). Significant coronary stenosis was found in 16.1% of nondiabetic group compared with 33.3% of diabetic group (P=0.0065). CONCLUSION: Our results show that the prevalence of coronary plaques detectable by 64-slice CT in asymptomatic diabetic patients is very high.

Comparison of the effects of nicorandil versus verapamil on the incidence of slow flow/no reflow during rotational atherectomy.

In rotational atherectomy, the slow-flow/no-reflow phenomenon is a common complication, which usually results in myocardial injury. We prospectively randomized 111 patients with successful rotational atherectomy into a verapamil group (group V, n = 56) and a nicorandil group (group N, n = 55). We compared final burr size, total ablation time, maximum decrease in revolutions per minute, incidence of slow flow/no reflow, creatine kinase-MB increase, and cardiac troponin T increase between the 2 groups. Patient and procedural characteristics were not significantly different between groups. The incidence of no reflow/slow flow was significantly lower in group N than in group V (3.6% vs 17.9%, respectively, p <0.05). The incidence of a minor increase in cardiac markers was also significantly lower in group N than in group V (creatine kinase-MB 3.6% vs 16.1%, p <0.05; cardiac troponin T 5.5% vs 21.4%, p <0.05). In conclusion, our results showed that nicorandil decreases the incidence of slow flow/no reflow during rotational atherectomy.