Prognostic Impacts of Comorbid Significant Coronary Stenosis and Coronary Artery Spasm in Patients With Stable Coronary Artery Disease.

BACKGROUND Stable coronary artery disease is caused by a variable combination of organic coronary stenosis and functional coronary abnormalities, such as coronary artery spasm. Thus, we examined the clinical importance of comorbid significant coronary stenosis and coronary spasm. METHODS AND RESULTS We enrolled 236 consecutive patients with suspected angina who underwent acetylcholine provocation testing for coronary spasm and fractional flow reserve (FFR) measurement. Among them, 175 patients were diagnosed as having vasospastic angina (VSA), whereas the remaining 61 had no VSA (non-VSA group). The patients with VSA were further divided into the following 3 groups based on angiography and FFR: no organic stenosis (≤50% luminal stenosis; VSA-alone group, n=110), insignificant stenosis of FFR>0.80 (high-FFR group, n=36), and significant stenosis of FFR≤0.80 (low-FFR group, n=29). The incidence of major adverse cardiovascular events, including cardiovascular death, nonfatal myocardial infarction, urgent percutaneous coronary intervention, and hospitalization attributed to unstable angina was evaluated. All patients with VSA received calcium channel blockers, and 28 patients (95%) in the low-FFR group underwent a planned percutaneous coronary intervention. During a median follow-up period of 656 days, although the incidence of major adverse cardiovascular events was low and comparable among non-VSA, VSA-alone, and high-FFR groups, the low-FFR group had an extremely poor prognosis (non-VSA group, 1.6%; VSA-alone group, 3.6%; high-FFR group, 5.6%; low-FFR group, 27.6%) (P<0.001). Importantly, all 8 patients with major adverse cardiovascular events in the low-FFR group were appropriately treated with percutaneous coronary intervention and calcium channel blockers. CONCLUSIONS These results indicate that patients with VSA with significant coronary stenosis represent a high-risk population despite current guideline-recommended therapies, suggesting the importance of routine coronary functional testing in this population.

Coronary Adventitial and Perivascular Adipose Tissue Inflammation in Patients With Vasospastic Angina.

BACKGROUND: Recent studies suggested that perivascular components, such as perivascular adipose tissue (PVAT) and adventitial vasa vasorum (VV), play an important role as a source of various inflammatory mediators in cardiovascular disease. OBJECTIVES: The authors tested their hypothesis that coronary artery spasm is associated with perivascular inflammation in patients with vasospastic angina (VSA) using 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT). METHODS: This study prospectively examined 27 consecutive VSA patients with acetylcholine-induced diffuse spasm in the left anterior descending artery (LAD) and 13 subjects with suspected angina but without organic coronary lesions or coronary spasm. Using CT coronary angiography and electrocardiogram-gated 18F-FDG PET/CT, coronary PVAT volume and coronary perivascular FDG uptake in the LAD were examined. In addition, adventitial VV formation in the LAD was examined with optical coherence tomography, and Rho-kinase activity was measured in circulating leukocytes. RESULTS: Patient characteristics were comparable between the 2 groups. CT coronary angiography and ECG-gated 18F-FDG PET/CT showed that coronary PVAT volume and coronary perivascular FDG uptake significantly increased in the VSA group compared with the non-VSA group. Furthermore, optical coherence tomography showed that adventitial VV formation significantly increased in the VSA group compared with the non-VSA group, as did Rho-kinase activity. Importantly, during the follow-up period with medical treatment, both coronary perivascular FDG uptake and Rho-kinase activity significantly decreased in the VSA group. CONCLUSIONS: These results provide the first evidence that coronary spasm is associated with inflammation of coronary adventitia and PVAT, where 18F-FDG PET/CT could be useful for disease activity assessment. (Morphological and Functional Change of Coronary Perivascular Adipose Tissue in Vasospastic Angina [ADIPO-VSA Trial]; UMIN000016675).

Low-energy cardiac shockwave therapy to suppress left ventricular remodeling in patients with acute myocardial infarction: a first-in-human study.

OBJECTIVE: Although primary percutaneous coronary intervention (PCI) substantially reduces the mortality of patients with acute myocardial infarction (AMI), left ventricular (LV) remodeling after AMI still remains an important issue in cardiovascular medicine. We have previously demonstrated that low-energy cardiac shockwave (SW) therapy ameliorates LV remodeling after AMI in pigs. In this first-in-human study, we examined the feasibility and the effects of the SW therapy on LV remodeling after AMI in humans. PATIENTS AND METHODS: Seventeen patients with AMI who successfully underwent primary PCI (peak-creatine kinase<4000 U/l) were treated with the SW therapy. Low-energy shock waves were applied to the ischemic border zone around the infarcted area at 2, 4, and 6 days since AMI. Next, we compared these patients with historical AMI controls by propensity score matching (N=25). RESULTS: There were no procedure-related complications or adverse effects. At 6 and 12 months after AMI, LV function as assessed by MRI showed no signs of deleterious LV remodeling. When we compared the SW-treated group with the historical AMI controls at 6 months after AMI, LV ejection fraction was significantly higher in the SW-treated group (N=7) than in the historical control group (N=25) by echocardiography (66±7 vs. 58±12%, P<0.05). LV end-diastolic dimension also tended to be smaller in the SW than in the control group (47.5±4.6 vs. 50.0±5.9 mm, P=0.29). CONCLUSION: These results suggest that low-energy extracorporeal cardiac SW therapy is feasible and may ameliorate postmyocardial infarction LV remodeling in patients with AMI as an adjunctive therapy to primary PCI.

Prognostic impacts of Rho-kinase activity in circulating leucocytes in patients with vasospastic angina.

Aims: Rho-kinase activity in circulating leucocytes is a useful biomarker for diagnosis and disease activity assessment of vasospastic angina (VSA). The present study aimed to examine the long-term prognostic impact of Rho-kinase activity in circulating leucocytes in VSA patients. Methods and results: We prospectively enrolled 174 consecutive patients with VSA and 50 non-VSA patients, in whom we measured Rho-kinase activity in circulating leucocytes, and they were followed for a median of 16 months. The primary endpoint was cardiac events including cardiac death, non-fatal myocardial infarction, and hospitalization for unstable angina. During the follow-up period, cardiac events occurred in 10 VSA patients (5.7%) but in none of the non-VSA patients. When we divided VSA patients into two groups by a median value of their Rho-kinase activity, the Kaplan-Meier survival analysis showed a significantly worse prognosis in VSA patients with high Rho-kinase activity compared with those with low activity or non-VSA patients (log-rank; P < 0.05, respectively). Receiver-operating characteristic curve analysis showed that Rho-kinase activity value of 1.24 was the best cut-off level to predict cardiac events in VSA patients, and multivariable analysis showed that a value above the cut-off point had the largest hazard ratio to predict poor outcome in VSA patients [hazard ratio (95% confidence interval) 11.19 (1.41-88.95); P = 0.022]. Importantly, combination of the Japanese Coronary Spasm Association risk score and Rho-kinase activity significantly improved the prognostic impact in VSA patients as compared with either alone. Conclusion: Rho-kinase activity in circulating leucocytes is useful for prognostic stratification of VSA patients.

Absence of adventitial vasa vasorum formation at the coronary segment with myocardial bridge - An optical coherence tomography study.

BACKGROUND: Myocardial bridge (MB) is a myocardial bundle through which coronary segment tunnels and could compress coronary arteries causing myocardial ischemia. However, the characteristic structural findings of MB remain to be fully elucidated. Recently, we demonstrated that optical coherence tomography (OCT) enables us to visualize adventitial vasa vasorum (VV) formation in humans. In this study, we examined adventitial VV formation at the coronary segment with MB in humans using OCT. METHODS: We examined 15 consecutive patients with suspected angina pectoris and MB in the left anterior descending (LAD) coronary arteries but no angiographic coronary stenosis. MB was detected on coronary angiography as a segment with milking effect. We performed intracoronary OCT imaging along the entire LAD. Morphometric analysis was performed at MB and proximal/distal segments at every 1mm. RESULTS: OCT examination showed the absence of adventitial VV formation at MB in the LAD, while VV was clearly noted at both the proximal and distal reference segments. Adventitial VV area was significantly less at MB compared with the proximal or distal references. CONCLUSIONS: These results with OCT imaging indicate that coronary segments with MB lack adventitial VV formation in humans, suggesting that MB could influence morphological and functional changes of the coronary artery.

Age-Specific Trends in the Incidence and In-Hospital Mortality of Acute Myocardial Infarction Over 30 Years in Japan　- Report From the Miyagi AMI Registry Study.

BACKGROUND: We are now facing rapid population aging in Japan, which will affect the actual situation of cardiovascular diseases. However, age-specific trends in the incidence and mortality of acute myocardial infarction (AMI) in Japan remain to be elucidated.Methods and Results:We enrolled a total of 27,220 AMI patients (male/female 19,818/7,402) in our Miyagi AMI Registry during the past 30 years. We divided them into 4 age groups (≤59, 60-69, 70-79 and ≥80 years) and examined the temporal trends in the incidence and in-hospital mortality of AMI during 3 decades (1985-1994, 1995-2004 and 2005-2014). Throughout the entire period, the incidence of AMI steadily increased in the younger group (≤59 years in both sexes), while in the elderly groups (≥70 years in both sexes), the incidence significantly decreased during the last decade (all P<0.01). In-hospital cardiac mortality significantly decreased during the first 2 decades in elderly groups of both sexes (all P<0.01), whereas no further improvement was noted in the last decade irrespective of age or sex, despite improved critical care of AMI. CONCLUSIONS: These results provide the novel findings that the incidence of AMI has been increasing in younger populations and decreasing in the elderly, and that improvement in the in-hospital mortality of AMI may have reached a plateau in all age groups in Japan.

Plasma concentration of serotonin is a novel biomarker for coronary microvascular dysfunction in patients with suspected angina and unobstructive coronary arteries.

AIMS: Although the importance of coronary microvascular dysfunction (CMD) has been emerging, reliable biomarkers for CMD remain to be developed. We examined the potential usefulness of plasma concentration of serotonin to diagnose CMD in patients with suspected angina and unobstructive coronary arteries. METHODS AND RESULTS: We enrolled 198 consecutive patients (M/F 116/82, 60.2 ± 13.3 years old) who underwent acetylcholine provocation test and measured plasma serotonin concentration. Coronary microvascular dysfunction was defined as myocardial lactate production without or prior to the occurrence of epicardial coronary spasm during acetylcholine provocation test. Although no statistical difference in plasma concentration of serotonin [median (inter-quartile range) nmol/L] was noted between the vasospastic angina (VSA) and non-VSA groups [6.8 (3.8, 10.9) vs. 5.1 (3.7, 8.4), P = 0.135], it was significantly higher in patients with CMD compared with those without it [7.7 (4.5, 14.2) vs. 5.6 (3.7, 9.3), P = 0.008]. Among the four groups classified according to the presence or absence of VSA and CMD, serotonin concentration was highest in the VSA with CMD group. Importantly, there was a positive correlation between plasma serotonin concentration and baseline thrombolysis in myocardial infarction frame count (P = 0.001), a marker of coronary vascular resistance. The classification and regression trees analysis showed that plasma serotonin concentration of 9.55 nmol/L was the first discriminator to stratify the risk for the presence of CMD. In multivariable analysis, serotonin concentration greater than the cut-off value had the largest odds ratio in the prediction of CMD [odds ratio (95% confidence interval) 2.63 (1.28-5.49), P = 0.009]. CONCLUSIONS: Plasma concentration of serotonin may be a novel biomarker for CMD in patients with angina and unobstructive coronary arteries.

Usefulness of Testing for Coronary Artery Spasm and Programmed Ventricular Stimulation in Survivors of Out-of-Hospital Cardiac Arrest.

BACKGROUND: Optimal therapy for patients resuscitated from out-of-hospital cardiac arrest (OHCA) who are not found to have structural heart disease remains to be established, especially regarding the use of implantable cardioverter-defibrillators. Coronary artery spasm (CAS) and lethal ventricular arrhythmias are important causes of OHCA. METHODS AND RESULTS: In 47 consecutive OHCA survivors without structural heart disease who had fully recovered (M/F 44/3, 43±13 years.), we performed dual induction tests, including acetylcholine provocation test first followed by programmed ventricular stimulation after 1 to 2 weeks. Patients with CAS were treated with calcium channel blocker-based antianginal medications; implantable cardioverter-defibrillators were implanted in all patients. The results of the dual induction tests defined 4 groups: CAS alone (n=7), inducible ventricular arrhythmias alone (n=13), both positive (n=24), and both negative (n=3). During a median follow-up period of 38 months, ventricular fibrillation recurred in all groups except the both-negative group. Of the 16 patients with a type I Brugada ECG, 2 had CAS alone, 8 had ventricular arrhythmias alone, and 6 had both positive. No ventricular fibrillation episodes were observed in the CAS-alone patients who did not also have Brugada syndrome. Kaplan-Meier analysis showed that the CAS-alone group was at lower risk for OHCA recurrence as compared with the Brugada syndrome group (log-rank test; P=0.036). CONCLUSIONS: Among OHCA survivors without structural heart disease, provokable CAS and ventricular arrhythmias are common and can be seen in Brugada syndrome. CAS alone without Brugada syndrome who are treated for CAS may be a lower-risk group.

Overview of the 80(th) Annual Scientific Meeting of the Japanese Circulation Society　- The Past, Present and Future of Cardiovascular Medicine in Japan -　- The 5(th) Anniversary of the Great East Japan Earthquake.

The 80(th)Annual Scientific Meeting of the Japanese Circulation Society was held in Sendai, Japan, on March 18-20, 2016, which coincided with the 5(th)anniversary of the Great East Japan Earthquake that hit the Tohoku area on March 11, 2011. Thus, the main themes for this meeting were "The Past, Present and Future of Cardiovascular Medicine in Japan" and "The 5(th)Anniversary of the Great East Japan Earthquake". Despite the provincial location, approximately 15,000 people attended during the 3-day meeting, and there were in-depth discussions in each of the various sessions on these themes. Especially, to our great pleasure, the Japanese Royals, Emperor Akihito and Empress Michiko, kindly visited the panel exhibition of the Great East Japan Earthquake and spoke words of appreciation to us. The meeting successfully completed and we sincerely appreciate the great cooperation and support from all affiliates. (Circ J 2016; 80: 1689-1694).

Beneficial effects of long-acting nifedipine on coronary vasomotion abnormalities after drug-eluting stent implantation: The NOVEL study.

AIMS: It is widely known that drug-eluting stents (DES) induce coronary vasomotion abnormalities. We have previously demonstrated that chronic treatment with long-acting nifedipine suppresses coronary hyperconstricting responses induced by the first-generation DES (e.g. sirolimus- and pacritaxel-eluting stents) through inhibition of vascular inflammation in pigs. To examine whether this is also the case with the second-generation DES (everolimus-eluting stents, EES) in humans, the most widely used DES in the world, we conducted a prospective, randomized, multicentre trial, termed as the NOVEL Study. METHODS AND RESULTS: We evaluated 100 patients with stable angina pectoris who underwent scheduled implantation of EES in the left coronary arteries. They were randomly assigned to receive either conventional treatments alone or additionally long-acting nifedipine (10-60 mg/day) (n = 50 each). After 8-10 months, 37 patients in the control and 38 in the nifedipine group were examined for coronary vasoreactivity to intracoronary acetylcholine (ACh) by quantitative coronary angiography after 48-h withdrawal of nifedipine. Coronary vasoconstricting responses to ACh were significantly enhanced at the distal edge of EES compared with non-stented vessel (P = 0.0001) and were significantly suppressed in the nifedipine group compared with the control group (P = 0.0044). Furthermore, the inflammatory profiles were also improved only in the nifedipine group, which evaluated by serum levels of high-sensitivity CRP (P = 0.0001) and adiponectin (P = 0.0039). CONCLUSIONS: These results indicate that DES-induced coronary vasomotion abnormalities still remain an important clinical issue even with the second-generation DES, for which long-acting nifedipine exerts beneficial effects associated with its anti-inflammatory effects. TRIAL REGISTRATION: This study is registered at the UMIN Clinical Trial Registry (UMIN-CTR; ID=UMIN000015147).

Increased Coronary Perivascular Adipose Tissue Volume in Patients With Vasospastic Angina.

BACKGROUND: Recent studies have suggested that coronary perivascular adipose tissue (PVAT) impairs coronary vasomotion, so we examined whether PVAT is increased at the spastic coronary segment in patients with vasospastic angina (VSA). METHODS AND RESULTS: PVAT volume in the left anterior descending (LAD) coronary arteries on CT coronary angiography was significantly increased in 48 VSA patients with LAD spasm compared with 18 controls (30.7±2.0 vs. 21.0±3.2 cm(3), P=0.01), whereas that of total epicardial adipose tissue was comparable between the 2 groups. CONCLUSIONS: The results suggested an important role of PVAT in the pathogenesis of coronary spasm. (Circ J 2016; 80: 1653-1656).

Beneficial Effects of a Novel Bioabsorbable Polymer Coating on Enhanced Coronary Vasoconstricting Responses After Drug-Eluting Stent Implantation in Pigs in Vivo.

OBJECTIVES: The aim of this study was to examine which component of drug-eluting stents (DES) plays a major role in enhanced coronary vasoconstricting responses after DES implantation in pigs. BACKGROUND: Recent studies have reported unremitting angina due to vasomotion abnormalities even after successful DES implantation. However, it remains to be elucidated which component of DES (metal stent, polymer coating, or antiproliferative drug) is responsible for DES-induced coronary hyperconstricting responses. METHODS: We developed poly-dl-lactic acid and polycaprolactone (PDLLA-PCL) copolymer technology with higher biocompatibility that is resorbed within 3 months. Four types of coronary stents were made: 1) a stent with polylactic acid (PLA) polymer coating containing antiproliferative drug (P1+D+); 2) a stent with PLA polymer coating alone without any drug (P1+D-); 3) a stent with novel PDLLA-PCL polymer coating alone (P2+D-); and 4) a bare metal stent (P-D-). The 4 stents were randomly deployed in the left anterior descending and left circumflex coronary arteries in 12 pigs. RESULTS: After 1 month, coronary vasoconstriction by intracoronary serotonin was enhanced at P1+D+ and P1+D- stent edges compared with P2+D- and P-D- stent edges and was prevented by a specific Rho-kinase (a central molecule of coronary spasm) inhibitor, hydroxyfasudil. Immunostainings showed that inflammatory changes and Rho-kinase activation were significantly enhanced at P1+D+ and P1+D- sites compared with P2+D- and P-D- sites. There were significant positive correlations between the extent of inflammation or Rho-kinase expression/activation and that of coronary vasoconstriction. CONCLUSIONS: These results indicate the important roles of PLA polymer coating in DES-induced coronary vasoconstricting responses through inflammatory changes and Rho-kinase activation in pigs in vivo, which are ameliorated by PDLLA-PCL copolymers.

Clinical Characteristics of Patients With Acute Myocardial Infarction Who Did Not Undergo Primary Percutaneous Coronary Intervention- Report From the MIYAGI-AMI Registry Study.

BACKGROUND: In the current era of primary percutaneous coronary intervention (PCI), some patients with acute myocardial infarction (AMI) still do not undergo primary PCI. METHODS AND RESULTS: To examine the clinical characteristics of AMI patients who did not undergo primary PCI, we analyzed patients enrolled between 2002 and 2010 in the MIYAGI-AMI Registry Study, in which all AMI patients in the Miyagi prefecture have been prospectively registered. Among a total of 8,640 patients, 1,879 (21.7%) did not undergo primary PCI and their in-hospital mortality was significantly worse compared with those who did (21.4% vs. 6.4%, P<0.01). Multivariate analysis demonstrated that female sex was significantly associated with non-performance of primary PCI [odds ratio (95% confidence interval): 1.40 (1.22-1.61), P<0.001], along with age [1.01 (1.01-1.02), P<0.001] and heart failure on admission [2.69 (2.29-3.16), P<0.001]. When dividing by age, the non-performance rate of primary PCI in females showed a U-shaped prevalence, whereas it simply increased with aging in males. Importantly, female patients aged <80 years had a significantly higher non-performance rate of primary PCI compared with male patients, regardless of the severity of AMI. CONCLUSIONS: These results indicate that in the current PCI era, various factors, including aging, heart failure on admission and sex differences, are associated with non-performance of primary PCI, which remain to be resolved in order to further improve critical care of AMI.

Association of Adventitial Vasa Vasorum and Inflammation With Coronary Hyperconstriction After Drug-Eluting Stent Implantation in Pigs In Vivo.

BACKGROUND: The importance of adventitial inflammation has been implicated for the pathogenesis of coronary artery disease. However, the roles of adventitial changes in drug-eluting stent (DES)-induced coronary hyperconstriction remain largely unknown. In the present study, this issue in pigs in vivo with a special reference to adventitial vasa vasorum (VV) formation and Rho-kinase activation, a central mechanism of coronary vasospasm, was examined. METHODS AND RESULTS: Each animal received a sirolimus-eluting stent (SES) and a biolimus A9-eluting stent (BES), one in the left anterior descending and another in the left circumflex coronary arteries in a randomized manner (n=18). After 1, 3 and 6 months, coronary vasomotion was examined. At 1 month, coronary vasoconstriction to serotonin was significantly enhanced at the SES edges as compared with the BES edges (SES, 52±7% vs. BES, 22±3%, P<0.01), which was equally prevented by a selective Rho-kinase inhibitor, hydroxyfasudil. A significant difference in vasoconstriction between SES and BES was sustained for 6 months. A micro-CT showed VV augmentation at the SES site, extending to the proximal and distal edges. Immunostainings demonstrated that VV formation, macrophage infiltration in the adventitia and Rho-kinase expressions/activation were significantly enhanced at the SES edges as compared with the BES edges. CONCLUSIONS: The DES with durable polymers enhances VV formation and inflammation in the adventitia, associating with the pathogenesis of DES-induced coronary hyperconstriction through Rho-kinase activation in pigs in vivo.

Accuracy of optical frequency domain imaging for evaluation of coronary adventitial vasa vasorum formation after stent implantation in pigs and humans - a validation study - .

BACKGROUND: Coronary adventitia harbors a wide variety of components, such as inflammatory cells and vasa vasorum (VV). Adventitial VV initiates the development of coronary artery diseases as an outside-in supply route of inflammation. We have recently demonstrated that drug-eluting stent implantation causes the enhancement of VV formation, with extending to the stent edges in the porcine coronary arteries, and also that optical frequency domain imaging (OFDI) is capable of visualizing VV in humans in vivo. However, it remains to be fully validated whether OFDI enables the precise measurement of VV formation in pigs and humans. METHODS AND RESULTS: In the pig protocol, a total of 6 bare-metal stents and 12 drug-eluting stents were implanted into the coronary arteries, and at 1 month, the stented coronary arteries were imaged by OFDI ex vivo. OFDI data including the measurement of VV area at the stent edge portions were compared with histological data. There was a significant positive correlation between VV area on OFDI and that on histology (R=0.91, P<0.01). In the human protocol, OFDI enabled the measurement of the VV area at the stent edges after coronary stent implantation in vivo. CONCLUSIONS: These results provide the first direct evidence that OFDI enables the precise measurement of the VV area in coronary arteries after stent implantation in pigs and humans.

Circadian variation of Rho-kinase activity in circulating leukocytes of patients with vasospastic angina.

BACKGROUND: Vasospastic angina (VSA) is known to exhibit circadian variation with an early morning peak. We examined whether Rho-kinase activity in circulating leukocytes, which is a useful biomarker for disease activity assessment of VSA, exhibits circadian variation in patients with VSA. METHODS AND RESULTS: In consecutive 31 VSA patients (M/F 23/8, 57±13 [SD] years) and 18 non-VSA patients (M/F 8/10, 57±14 years), we measured Rho-kinase activity in circulating leukocytes at 6:00, 12:00 and 21:00. We also examined the relationship between the Rho-kinase activity and coronary vasomotor responses during provocation test. Rho-kinase activity was significantly higher in VSA patients than in non-VSA patients at 6:00 (1.17±0.17 vs. 0.92±0.22, P<0.001), and showed a significant circadian variation with a peak at 6:00 (1.00±0.15 at 21:00, 1.17±0.17 at 6:00 and 1.12±0.22 at 12:00, P<0.001) in VSA patients, whereas no such variation was noted in non-VSA patients. Importantly, Rho-kinase activity at spasm provocation test was significantly correlated with basal coronary tone defined by vasodilating responses to intracoronary nitrate (r=0.40, P<0.05) and coronary vasoconstricting responses to acetylcholine (r=0.44, P<0.05) in VSA patients. Furthermore, their Rho-kinase activity at 6:00 was positively correlated with nocturnal parasympathetic activity as evaluated by heart rate variability in Holter monitoring (r=0.48, P<0.05). CONCLUSIONS: Rho-kinase activity exhibits distinct circadian variation associated with alterations in coronary vasomotor responses and autonomic activity in VSA patients.