Clinical significance of corrected relative flow reserve derived from 13N-ammonia positron emission tomography combined with coronary computed tomography angiography

BACKGROUND

This study evaluated corrected relative flow reserve (RFR) derived from 13N-ammonia positron emission tomography (PET) combined with coronary computed tomography angiography (CTA).

METHODS

We analyzed 61 patients who underwent coronary CTA, 13N-ammonia PET, and invasive coronary angiography. Triple-vessel disease were excluded. Conventional RFRs were calculated as the ratio of hyperemic myocardial blood flow (hMBF) of hypoperfusion areas to those of non-ischemic lesions. Corrected RFRs were calculated using PET and coronary CTA to adjust coronary territories to their feeding vessels. Diagnostic performance was compared to detect obstructive coronary lesions.

RESULTS

Of the 180 vessels analyzed, 50 were diagnosed as obstructive lesions (≥ 70% stenosis and/or fractional flow reserve value ≤ 0.8). The coronary flow reserve (CFR), hMBF, conventional RFR, and corrected RFR of obstructive lesions were significantly lower than those of non-obstructive lesions. In receiver operating characteristic curve analysis, these quantitative PET measurements had area under the curve of 0.67, 0.71, 0.89, and 0.92, respectively. Diagnostic performance differences between corrected and conventional RFR were not statistically significant.

CONCLUSION

In patients with single or double vessel disease, indices of RFR, with or without coronary angiographic guidance of the reference coronary territory, are better discriminators of flow-limiting stenoses than hMBF and CFR.

Clinical usefulness of relative apical sparing pattern for predicting functional recovery after transcatheter aortic valve implantation in patients with severe aortic stenosis

Background

Relative apical sparing pattern (RASP) is thought to be associated with prognosis in patients with cardiac amyloidosis or left ventricular hypertrophy (LVH). Although almost all patients with severe aortic stenosis (AS) have LVH, little is known about the effect of transcatheter aortic valve implantation (TAVI) in patients with severe AS exhibiting a RASP.

Purpose

This study aimed to elucidate the effect of TAVI on left ventricular global longitudinal strain (LS; LVGLS) in patients with severe AS exhibiting a RASP.

Methods

Eighty-four patients who underwent transfemoral or subclavian TAVI were evaluated. They were divided into the RASP and non-RASP groups. The average apical LS divided by the sum of the average mid and basal LS values of >1.0 was defined as the RASP. We analyzed the difference between pre- and post-TAVI LVGLS (ΔGLS = post-TAVI LVGLS − pre-TAVI LVGLS).

Results

Of the 84 patients (mean age, 84.5±3.9 years; 24 men), 15 (17.9%) exhibited a RASP. No significant difference in mean pre-TAVI LVGLS was found between the RASP and non-RASP groups (−16.6% ± 3.8% vs. −15.8% ± 3.9%). The ΔGLS in the RASP group was significantly higher than that in the non-RASP group (−0.97% ± 2.5% vs. −2.6% ± 3.0%; P<0.05). Multivariate analysis revealed that relative apical longitudinal strain was an independent predictor of ΔGLS (β = 0.35, p=0.002).

Conclusion

Relative apical longitudinal strain was associated with LVGLS recovery. The effect of TAVI on LVGLS in patients with a RASP is inferior to that in patients without a RASP.

Funding Acknowledgement

Type of funding source: None

P6005Incidence and clinical characteristics of coronary artery spasm in patients with out-of-hospital cardiac arrest

Background

Substantial cases of out-of-hospital cardiac arrest (OHCA) due to acute coronary syndrome have been recognized thus far, but there have been few reports about the aetiology of patients with OHCA without the organic heart disease. Especially, coronary artery spasm would be one of the causes of OHCA.

Purpose

This study aimed to investigate causes of OHCA without the organic heart disease and to investigate the characteristics and angiographic findings of OHCA patients with vasospastic angina (VSA).

Methods

Between January 2010 and April 2018, 920 patients with OHCA caused by probable or definite cardiovascular disease were transferred to our hospital. Return of spontaneous contraction was successfully achieved in 151 patients, among whom diagnosis was made in 130 patients. First, we analysed the causes of OHCA in these patients. Second, we compared clinical and angiographic characteristics between the VSA group with OHCA (OHCA-VSA) and the VSA group without OHCA (stable VSA; n=72) from our database.

Results

Among the 130 patients, 95 (73%) had the organic heart disease; 72, acute coronary syndrome; 19, myocardial disease; 2, valvular heart disease; and 1, congenital heart disease. There were 35 patients (27%) without the organic heart disease. Nineteen patients had primary (i.e., Brugada syndrome, QT prolongation) or secondary arrhythmia (i.e. drug adverse effect). Electrocardiogram, coronary angiogram, and LV structure and function were normal in 35 patients. However, there were 16 patients (11%) with VSA defined by Japanese guideline. The OHCA-VSA group was significantly younger (50±14) than the stable VSA group (64±11, P=0.003). The incidence of diffuse-type spasm in the OHCA-VSA group (100%) was significantly higher than that in the stable VSA group (100% vs. 69%, P<0.05). In addition, the incidence of triple-vessel coronary spasm in the OHCA-VSA group was significantly higher than that in the stable VSA group (86% vs. 25%, P=0.003).

Conclusion

OHCA patients without the organic heart disease had considerable cases of VSA, in addition to primary or secondary arrhythmia. Furthermore, the severity of spasm in the OHCA-VSA group was more serious and extensive than in comparison with the stable VSA group.

A unique case of ST-elevation myocardial infarction related to very late stent thrombosis

A 67-year-old man was transferred to our hospital because of anterior ST elevation myocardial infarction (STEMI). He had a history of a sirolimus-eluting stent implantation from the left main to the left anterior descending coronary artery (LAD) 9 years before and had undergone laparoscopic prostatectomy 8 days before in the setting of discontinuation of dual antiplatelet therapy. Emergent coronary angiography showed total occlusion in the distal LAD that was successfully treated by aspiration alone. Optical coherence tomography (OCT) showed no vulnerable lesion from the occluded lesion to the proximal LAD. OCT demonstrated that the thrombus attached to floating struts at the left main bifurcation and non-apposed struts at the left coronary ostium partly protruding to aorta, while the other struts were covered and well-apposed. Based on OCT findings, this case of STEMI was thought to be caused by distal embolism of a thrombus that formed at the stent site before it evolved into total occlusion. <Learning objective: We demonstrated how optical coherence tomography can be essential in revealing the underlying pathology. The patient showed an unusual manifestation of ST-elevation myocardial infarction caused by distal embolism of a thrombus that formed at the sirolimus-eluting stent due to dual antiplatelet therapy discontinuation during perioperative period. Optical coherence tomography revealed very late stent thrombosis at the left coronary ostium and could elucidate the underlying mechanism.>.

The feasibility of substituting left atrial wall strain for flow velocity of left atrial appendage

OBJECTIVE

Non-valvular atrial fibrillation (NVAF) is frequently complicated by thromboembolism. Left atrial appendage (LAA) flow is a predictor of LAA thrombosis. LAA flow is measured by transesophageal echocardiography (TEE), which is a semi-invasive diagnostic tool. Recently, speckle-tracking methods have been adapted for the evaluation of local cardiac function. We hypothesised that if we could determine LAA wall motion utilising a speckle tracking technique, we could non-invasively analyse LAA flow.

METHODS

Sixty-three NVAF patients including 38 with chronic atrial fibrillation (CAF), 14 with paroxysmal AF (PAF) and 11 with atrial flutter (AFL) were enrolled in this study. Normal sinus rhythm (NSR) patients with non-thromboembolic cerebral infarction were also included. Immediately after obtaining a 2D movie of the LAA through the aortic oblique short axis view by transthoracic echocardiography, LAA flow velocity was measured by TEE. Mean strains between the posterior and anterior walls were measured using a speckle-tracking technique.

RESULTS

Ten patients exhibited a thrombus and 11 had spontaneous echo contrast (SEC) in the auricle. Mean strain value was similar between CAF and PAF, although LAA flow velocity for CAF was significantly reduced compared with PAF (median value 13.7 cm/s versus 36.1 cm/s, p = <.00001). Mean strain of CAF with thrombus/SEC was significantly reduced compared with NSR patients (median value 1.52% versus 3.17%, p = .00181). Furthermore, mean strain was correlated with LAA flow velocity (R = 0.399, R2 = 0.1595, p = .000615).

CONCLUSIONS

LAA wall strain identified via speckle-tracking methods may presage LAA peak flow velocity. This technique may contribute to stratification of thrombosis risks in the LAA.

Isolated Left Atrial Infective Mural Endocarditis

A 52-year-old man presented with a fever and malaise. Transthoracic echocardiogram was performed because of a holosystolic murmur, which showed mitral valve prolapse and a regurgitation jet toward the posterior wall of the left atrium. There was no apparent vegetation at any valves. Blood cultures were positive for Streptococcus mitis/oralis. Transesophageal echocardiogram revealed vegetation only at the posterior wall of the left atrium exposed to the mitral regurgitant jet. We diagnosed this condition as infective mural endocarditis. This case highlighted the need for a detailed observation of the valves and the atrial wall when infective endocarditis is suspected.

Beneficial effects of adaptive servo-ventilation therapy on readmission and medical costs in patients with chronic heart failure

Adaptive servo-ventilation (ASV) therapy is a novel modality of noninvasive positive pressure ventilation and is now widely utilized to treat patients with chronic heart failure (CHF). However, there has been no clinical study of the effect of ASV therapy on readmission and cost-effectiveness for the treatment of CHF. The present study was conducted to evaluate the clinical efficacy and cost-effectiveness of home ASV therapy in 45 patients with a history of two or more admissions a year for worsening CHF. Seven patients refused to undergo chronic ASV therapy and three died. Thus, 35 patients were eventually enrolled in the present study. New York Heart Association class (2.8 ± 0.4 versus 2.3 ± 0.5, p < 0.001), log plasma B-type natriuretic peptide level (2.53 ± 0.44 versus 2.29 ± 0.40 pg/mL, p < 0.0001), left atrial dimension (47.5 ± 7.0 versus 44.9 ± 7.6 mm, p = 0.014), and mitral regurgitation area ratio (20.3 ± 12.1 versus 16.9 ± 8.9%, p = 0.007) decreased significantly after 12 months of ASV therapy. The frequency of hospitalization after ASV was significantly lower than before ASV (1.0 ± 1.0 versus 2.3 ± 0.5 times/year/patient, p < 0.0001). ASV also decreased the duration of hospitalization from 64.4 ± 46.5 to 22.8 ± 27.5 days/year/patient (p < 0.0001). Consequently, the total medical costs were reduced by 37% after ASV (1.95 ± 1.37 versus 3.11 ± 1.75 million yen/patient, p = 0.003). ASV therapy reduced readmissions and medical costs in patients with CHF.

Favorable effects of early tolvaptan administration in very elderly patients after repeat hospitalizations for acute decompensated heart failure

Tolvaptan (TLV) is an oral selective vasopressin 2 receptor antagonist that acts on the distal nephrons, causing a loss of electrolyte-free water. To date, its early administration in very elderly patients after repeat hospitalizations for acute decompensated heart failure (ADHF) despite receiving optimal medical therapy has not been evaluated. Fifty-six ADHF patients who were >80 years old and had been repeatedly hospitalized were retrospectively enrolled in this study. Twenty-five patients (14 men; mean age 86.7 ± 5.3 years; control group) received standard therapy and 31 patients (15 men; mean age 85.5 ± 4.5 years; TLV group) received oral TLV within 24 h of admission. The rate of worsening renal function was significantly lower in the TLV group than in the control group (13 vs. 40%, P < 0.05). The duration of the return to body weight at a steady state was significantly shorter in the TLV group (5.3 ± 2.8 days) than in the control group (13.9 ± 9.2 days, P < 0.01). Consequently, the hospitalization period in the TLV group (13.5 ± 5.9 days) was significantly shorter than that in the control group (24.7 ± 12.3 days, P < 0.01). In conclusion, the early administration of TLV to very elderly patients who underwent repeat hospitalizations for ADHF resulted in immediate decongestion and thus reduced the hospitalization period with a lower incidence of worsening renal function.

Prevention of Positive Coronary Artery Remodeling with Statin Therapy in Patients with Coronary Artery Diseases

Since positive coronary artery remodeling with large plaque burden is associated with subsequent coronary events, the authors tested their hypothesis that secondary prevention of coronary events by a statin may be associated with inhibition of the process of positive coronary artery remodeling in underlying coronary atherosclerotic lesions in patients with coronary artery diseases. They evaluated the intravascular ultrasound imaging in angiographically normal coronary lesions at baseline and after 6 months of therapy in 64 patients with coronary artery diseases. External elastic membrane area was defined as the vessel area, and the difference between the vessel and lumen area was calculated as plaque area. The relative echogenicity of coronary plaque to adventitia was evaluated as acoustic characteristics of coronary plaque. Twenty-five patients were treated with a statin and 39 patients did not receive a statin. In patients treated with a statin, plaque area decreased by 12% (p=0.013) compared to an increase in plaque area of 13% (p=0.023) in those who did not receive a statin. The vessel area was not enlarged in patients treated with a statin but did show positive remodeling in patients who had plaque progression without a statin. The relative echogenicity of plaque was unchanged in patients treated with a statin but significantly decreased in patients not receiving a statin. A statin may prevent positive coronary artery remodeling via inhibition of plaque progression in underlying coronary atherosclerotic lesions in patients with coronary artery diseases.

Systemic Versus Coronary Levels of Inflammation in Acute Coronary Syndromes

To address a possible link between systemic and coronary inflammation in the setting of acute coronary syndromes, the authors examined both levels of 3 inflammatory mediators such as high sensitive C-reactive protein (hs-CRP), interleukin (IL)-6, and matrix metalloproteinase (MMP)-9 in patients with the early phase of acute myocardial infarction (AMI). In total, 20 patients with AMI showing minimal elevation of cardiac enzymes were studied. Before angioplasty, peripheral blood and culprit coronary thrombus were sampled to compare systemic and coronary levels of hs-CRP, IL-6, and MMP-9. Relation of systemic levels of hs-CRP and IL-6 to culprit coronary morphology was also evaluated by the use of intravascular ultrasound. Systemic and coronary levels of hs-CRP were nearly equivalent (4.3 ±5.0 vs 4.7 ±5.4 mg/L, p=0.279), whereas IL-6 and MMP-9 showed higher in coronary levels than in systemic levels (169 ±154 vs 93 ±107 pg/mL, p=0.002 and 164 ±116 vs 103 ±94 ng/mL, p=0.018, respectively). Systemic levels of hs-CRP were correlated with coronary levels of IL-6 (r =0.566, p=0.009). Culprit coronary plaque area demonstrated a positive relation with systemic levels of hs-CRP (r =0.466, p=0.038) and also IL-6 (r =0.707, p<0.001). The present study may provide an important insight into the link between systemic and coronary levels of inflammation, which is also associated with vulnerable coronary morphology in the setting of acute coronary syndromes.

A calcified amorphous tumor that developed on both sides of the atrioventricular valve annulus

We report a rare case of a hemodialysis patient with a calcified amorphous tumor (CAT) on both sides of the atrioventricular valve annulus. A 70-year-old female who had received hemodialysis for 23 years because of chronic glomerulonephritis presented to our hospital with acute heart failure. Echocardiography indicated the presence of mobile cardiac masses on the mitral valve and tricuspid valve annulus. We suspected the presence of a cardiac tumor or vegetation. The patient received 3 g/day sulbactam-ampicillin and 60 mg/day gentamicin. Surgery was performed on the 14th day after hospital admission. The patient underwent mitral valve replacement, tricuspid annuloplasty, and tumor resection. Based on the pathological findings, the cardiac tumor was diagnosed as a CAT.

Contrast-enhanced ultrasound for the evaluation of acute renal infarction

A 65-year-old male in the dilated phase of hypertrophic cardiomyopathy and with persistent atrial fibrillation was admitted to our hospital because of an episode of ventricular fibrillation following an appropriate shock from an implantable cardiac defibrillator (ICD). At admission, electrocardiography showed a normal sinus rhythm. He had complained of back pain 7 days after the ICD shock. Renal infarction was suspected, although computed tomography and magnetic resonance imaging could not be performed because of chronic renal failure and the presence of his ICD. We, therefore, used contrast-enhanced ultrasonography with a contrast agent to evaluate his acute kidney injury. This showed the left kidney contained a wedge-shaped area that was not enhanced by the contrast agent, indicating an area of infarction.

Impact of chronic total coronary occlusion on microvascular reperfusion in patients with a first anterior ST-segment elevation myocardial infarction

BACKGROUND

We investigated an impact of the presence of chronic total coronary occlusion (CTO) in a non-infarct related coronary artery on microvascular reperfusion in patients with a first anterior ST-segment elevation myocardial infarction (STEMI) who underwent percutaneous coronary intervention (PCI).

METHODS

In accordance with the presence or absence of CTO in a non-infarct related coronary artery, we analyzed Thrombolysis in Myocardial Infarction myocardial perfusion (TMP) grade on a scale of 0 to 3, with higher scores indicating better perfusion, and ST-segment resolution in sum of lead I, aVL, and V1 through V6 to evaluate microvascular reperfusion in a total of 140 consecutive patients with a first anterior STEMI.

RESULTS

We identified CTO in 15 patients (11% of total). The incidence of impaired microvascular reperfusion was greater in patients with CTO vs without CTO, defined as TMP grades 0 or 1 together with <30% ST-segment resolution (33% vs 6%, respectively; P=.0006) and the enzymatic infarct was larger (10304 ± 8060 IU/L vs 6804 ± 4959 IU/L; P=.009). Logistic regression analysis revealed that CTO is closely associated with incidental impaired microvascular reperfusion (odds ratio, 6.801; 95% confidence interval, 1.284-36.209; P=.024).

CONCLUSION

The presence of CTO in a non-infarct related coronary artery might confer a considerable disadvantage upon microvascular reperfusion and result in adverse clinical outcomes of PCI for a first anterior STEMI.

Prognostic utility of T-wave alternans in a real-world population of patients with left ventricular dysfunction: the PREVENT-SCD study

BACKGROUND

The predictive value of T-wave alternans (TWA) for lethal ventricular tachyarrhythmia in patients with left ventricular (LV) dysfunction is controversial. Also, long-term arrhythmia risk of patients ineligible for the TWA test is unknown.

METHODS

This was a multicenter, prospective observational study of patients with LV ejection fraction ≤40% due to ischemic or non-ischemic cardiomyopathies, designed to evaluate the prognostic value of TWA for lethal ventricular tachyarrhythmia. The primary end point was a composite of sudden cardiac death, sustained rapid ventricular tachycardia (VT) or ventricular fibrillation (VF), and appropriate defibrillator therapy for rapid VT or VF.

RESULTS

Among 453 patients enrolled in the study, 280 (62%) were eligible for the TWA test. TWA was negative in 82 patients (29%), who accounted for 18% of the total population. The median of follow-up was 36 months. The 3-year event-free rate for the primary end point was significantly higher in TWA-negative patients (97.0%) than in TWA non-negative patients (89.5%, P = 0.037) and those ineligible for the TWA test (84.4%, P = 0.003). Multivariable analysis identified both non-negative TWA [hazard ratio (HR) 4.43; 95% confidence interval (CI) 1.02-19.2; P = 0.047) and ineligibility for the TWA test (HR 6.89; 95% CI 1.59-29.9; P = 0.010) to be independent predictors of the primary end point.

CONCLUSIONS

TWA showed high negative predictive ability for lethal ventricular tachyarrhythmia in patients with LV dysfunction, although the TWA-negative patients accounted for only 18% of the entire population. Those ineligible for the TWA test had the highest risk for lethal ventricular tachyarrhythmia.

Brain natriuretic peptide as a risk marker for incident hypertensive cardiovascular events

We examined the effects of aging and hypertensive left ventricular hypertrophy on the plasma level of brain natriuretic peptide (BNP), and assessed BNP as a risk marker for incident hypertensive cardiovascular events. One hundred and eighty-five hypertensive patients were echocardiographically divided into a hypertensive group with normal left ventricular mass (n=96; age range, 37-86 years; left ventricular mass, 97+/-14 g/m2) and a hypertensive group with left ventricular hypertrophy (n=89; 37-90 years; 140+/-20 g/m2). Forty-four normotensive subjects served as the normotensive group (32-84 years; 91+/-15 g/m2). We examined the association of age with BNP in the three groups and also evaluated BNP as a risk marker for incident cardiovascular events by following up all patients for 40 months. All three groups demonstrated a significant positive relationship between age and BNP. The slope of the relation between age and BNP was steepest in the hypertensive group with left ventricular hypertrophy (p<0.0001 vs. the other two groups). Multiple regression analysis revealed that age, pulse pressure and left ventricular mass index were significantly associated with the increase in BNP. Multivariate Cox proportional hazards regression analysis, which was used to assess the potential association of age, pulse pressure, left ventricular mass index and BNP with the cardiovascular events during follow-up, revealed the highest correlation between BNP and incident cardiovascular events (risk ratio=1.011; p=0.0011). BNP, which is synergistically increased with aging and left ventricular hypertrophy, may be an important risk marker for hypertensive cardiovascular events.

Left ventricular volumes, ejection fraction, and regional wall motion calculated with gated technetium-99m tetrofosmin SPECT in reperfused acute myocardial infarction at super-acute phase: comparison with left ventriculography

BACKGROUND

Noninvasive assessment of acute myocardial infarction (AMI) requires information about both myocardial perfusion and left ventricular (LV) function. The automated quantification of electrocardiographic-gated myocardial scintigraphy with technetium-99m tetrofosmin (QGS) can provide this information.

METHODS AND RESULTS

Coronary arteriography, QGS, and left ventriculography (LVG) were performed in 229 patients with reperfused AMI within 2 days after onset. All infarcted vascular territories (229 segments) were visualized with scintigraphic perfusion images. The mean wall motion score (WMS) was 15.9+/-2.8 by means of QGS and 16.3+/-2.9 by means of LVG. The correlation between WMS obtained by means of QGS and that obtained by means of LVG was close (y = 0.913x + 1.016, r = 0.94, P<.001), but that obtained by means of QGS was significantly lower than that obtained by means of LVG (P<.0001). Total agreement for the assessment of regional wall motion reached 75 % (kappa, 0.66). Although the LV values obtained by means of QGS and LVG correlated well (end-diastolic volume, r = 0.67, P<.0001; end-systolic volume, r = 0.79, P<.0001; ejection fraction, r = 0.78, P<.0001), end-diastolic volume and ejection fraction tended to be underestimated with QGS.

CONCLUSION

QGS data were considered to be useful in detecting infarcted vascular territory and LV function, even in AMI, within 2 days after onset.

The effect of coronary vasospasm on the direction of ST-segment deviation in patients with both hypertrophic cardiomyopathy and vasospastic angina

BACKGROUND

There has been no report of ECG changes during anginal attacks in patients with coexistent hypertrophic cardiomyopathy (HCM) and vasospastic angina.

STUDY OBJECTIVES

To elucidate the change in ST-segment during anginal attacks in patients with coexistent HCM and vasospastic angina (the HCM group) in comparison with that of patients with vasospastic angina and no left ventricular hypertrophy (the non-HCM group).

DESIGN

Retrospective study.

PATIENTS

Twelve patients in the HCM group, and 28 patients in the non-HCM group.

MEASUREMENTS

The direction of ST segment shift, either ST-segment elevation or depression, on the ECGs recorded during vasospastic anginal attacks with severe vasoconstriction in the epicardial coronary artery after intracoronary injection of acetylcholine.

RESULTS

Age, male gender, and distribution of coronary arteries in which the vasospasm occurred were similar between the two groups. Collateral circulation to the affected arteries was absent in all the study patients. The prevalence of anginal attacks associated with ST-segment elevation was 2.7 times higher in the non-HCM group than in the HCM group (51. 5% [17 of 33 attacks] vs 18.8% [3 of 16 attacks], respectively; p = 0.03).

CONCLUSIONS

In the HCM group, myocardial ischemia associated with a transmural injury pattern seen on the ECG, which is represented as ST-segment elevation, seldom develops during vasospastic anginal attacks because of marked left ventricular hypertrophy.

Clinical characteristics in Japanese patients with coexistent hypertrophic cardiomyopathy and coronary vasospasm

There are only a few reports concerning coexistent hypertrophic cardiomyopathy (HCM) and vasospastic angina. Clinical characteristics in patients with both diseases have not been clarified yet. This study was designed to elucidate the relationship between chest pain and coronary vasospasm in HCM patients and to delineate clinical characteristics in patients with both HCM and coronary vasospasm. First, 36 patients with HCM underwent acetylcholine provocation test for coronary vasospasm and were divided into two groups on the basis of presence or absence of coronary vasospasm. Next, the following risk factors for coronary artery disease were compared between the two groups: hypertension, smoking, hyperlipidemia, diabetes mellitus, and hyperuricemia. Coronary vasospasm was induced in 10 (28%) of 36 patients with HCM. There were no significant differences in age and male gender between the two groups. Smoking was more prominent in HCM patients with than without coronary vasospasm (80% vs 35%, p<0.05), but there were no differences in the prevalence of other risk factors between the two groups. In conclusion, coronary vasospasm appears to play a significant role in the etiology of myocardial ischemia in Japanese patients with HCM, and smoking might be a major risk factor for coexistence of HCM and coronary vasospasm.

[Effective low-dose amiodarone therapy for ventricular tachycardia complicated with ischemic heart disease and poor left ventricular function in an elderly patient]

A 71-year-old man who had ischemic heart disease with poor left ventricular function and ventricular tachycardia was admitted to hospital for evaluation. Cardiac catheterization was performed on August 19, 1996, and right coronary arteriography revealed total occlusion at segment 3. Left coronary arteriography revealed total occlusion at segment 6, and a lesion at segment 13 was 75% occluded. Partial collateral flow from the right ventricular branch to the left anterior descending artery was demonstrated, and the left ventricular ejection fraction was 24%. Recurrent ventricular tachycardia followed by pre-syncope occurred from August 23, 1996, and the patient underwent emergency coronary artery bypass surgery to the left anterior descending artery and circumflex artery using saphenous vein grafts. Ventricular tachycardia followed by pre-syncope occurred frequently after the bypass surgery, and antiarrhythmic agents (Vaughan Williams classification Ia and Ib groups) were ineffective. He received amiodarone (100 mg/day after a loading dose of 200 mg/day for 2 weeks) from September 6, 1996. His symptoms of arrhythmia decreased, and side effects have not been observed. Low-dose amiodarone was effective in this case of ischemic heart disease with left ventricular dysfunction and sustained ventricular tachycardia.

[Mitral prosthetic valve replaced twice due to repeated prosthetic valve endocarditis: a case report]

A 38-year-old man was admitted to our hospital for detailed examination of fever, cough and yellow sputum. At the age of 32, be had mitral prosthesis for the first time, because of mitral regurgitation due to mitral valve prolapse. Four years previously, he had again undergone mitral prosthetic valve replacement due to prosthetic valve endocarditis due to staphylococcus epidemidis. This occasion, staphylococcus aureus was isolated by arterial blood culture. Transesophageal echocardiography detected vegetation attached to the mitral prosthetic valve and paravalvular leakage. The diagnosis was prosthetic valve endocarditis. He underwent a third mitral prosthetic valve replacement. Detection of the source of infection was difficult only by transthoracic echocardiography, and immediate transesophageal echocardiography seemed mandatory to diagnose bacterial endocarditis.

[Evaluation of myocardial damage using 123I-BMIPP imaging in patients with vasospastic angina]

The purpose of this study is to determine whether left ventricular dysfunction following coronary artery spasm by 123I-BMIPP myocardial imaging. To reveal the clinical efficacy of 123I-BMIPP SPECT, 20 patients with vasospastic angina were studied using resting, 3-hour delayed image with 123I-BMIPP and exercise, 3-hour delayed image with 201Tl SPECT. 123I-BMIPP uptake was decreased compared to 201Tl (discordant) in 12 patients (60%) and in 49/100 myocardial segments (49%). The extent and severity score in resting image with 123I-BMIPP were significantly larger than that in delayed image with 201Tl (p < 0.01). In 123I-BMIPP SPECT, the severity score in the latest ischemia were significantly larger than that in others. The incidence of a complete agreement of decreased 123I-BMIPP uptake and coronary artery spasm was significantly higher (75%) than that in 201Tl (28%, p < 0.01). Furthermore, compared to 201Tl uptake, decreased 123I-BMIPP uptake much more corresponded to reduced wall motion in 9 of patients with mismatching. The severity of regional wall motion abnormality was significantly correlated with severity score of 123I-BMIPP. Late redistribution in delayed image with 123I-BMIPP was seen in 6 patients. The regional washout rate and the severity of regional wall motion abnormality in 6 patients was significantly lower than that in others (p < 0.05). Thus, metabolic abnormality assessed by 123I-BMIPP is well associated with left ventricular asynergy and spastic region in patients with vasospastic angina. In conclusion, 123I-BMIPP SPECT may sensitively delineate the impaired myocardium following coronary artery spasm, and it is very useful in diagnosing and estimating the severity of vasospastic angina.

Clinical significance of pressor responses to laboratory stressor testing in hypertension

We investigated the relation between pressor responses to laboratory stressors and 24-hour blood pressure (BP) variability or left ventricular mass. Mental arithmetic tests, isometric hand grip exercise, and bicycle ergometer exercise were carried out in middle-aged normotensive subjects (n=10) and in age-matched WHO stage I (n=23) and stage II (n=11) patients with essential hypertension. Mental arithmetic was associated with a greater rate of increase in plasma epinephrine than in norepinephrine, and handgrip exercise was associated with a greater rate of increase in plasma norepinephrine than in epinephrine in all three groups. Bicycle ergometer exercise caused a remarkable increase in plasma norepinephrine and a mild increase in plasma epinephrine in all three groups. In mental arithmetic tests, pressor responses of hypertensive patients were significantly greater than those of normotensives. The pressor response during mental tests was significantly correlated with the value of 24-hour BP variability in all subjects (r=0.56, p< 0.01). The pressor response to handgrip increased with the stage of hypertension. A good correlation existed between the pressor response to handgrip and the left ventricular mass index in the subjects (r=0.73, p < 0.001). There was no difference in the pressor response to ergometer exercise between any of the groups. The findings suggest that the pressor response to mental stress reflects BP variability and that the response to handgrip is correlated with target-organ disease associated with hypertension, especially the degree of cardiac hypertrophy.

Detection of perioperative coronary vasospasm on iodine-123-MIBG, thallium-201 and iodine-123-BMIPP myocardial SPECT images

A 64-yr-old woman, who had no history of anginal attack, underwent cholecystectomy under general anesthesia. A few hours after successful surgery, the EKG showed T-wave inversions with QT-interval prolongations and torsades de pointes. The [123I]MIBG scintigraphic findings revealed marked denervation in the anteroseptal and inferoposterior myocardium, whereas 201TI myocardial SPECT showed only slightly reduced tracer uptake in those areas. The [123I]BMIPP scans showed abnormal fatty acid metabolism in the anteroseptal myocardium. Coronary angiogram detected no fixed stenosis, but coronary vasoconstriction in the left anterior descending artery was induced by intracoronary injection of acetylcholine. In our patient, the findings of cardiac imaging with [123I]MIBG, 201TI and [123I]BMIPP led to coronary angiography and the final diagnosis of probable perioperative coronary vasospasm.

Vasospastic angina in two sisters

Vasospastic angina was observed in two sisters. The 52-year-old younger sister presented with rest angina at midnight and in the early morning. The coronary arteriogram showed no significant organic stenosis. Vasospasm to the left anterior descending and right coronary arteries was induced by the intracoronary administration of acetylcholine. The 57-year-old elder sister complained of rest and effort angina. Her coronary arteriogram was also normal. Vasospasm to the left circumflex and right coronary arteries was provoked by acetylcholine. In both cases, human leukocyte antigen DQw3 was negative. In the present cases, genetic factors may partly contribute to the mechanism of vasospastic angina.