Giulia Famoso

Coronary Microvascular Dysfunction Induced by Primary Hyperparathyroidism is Restored After Parathyroidectomy

Background— Symptomatic primary hyperparathyroidism (PHPT) is associated with increased cardiovascular mortality. However, data on the association between asymptomatic PHPT and cardiovascular risk are lacking. We assessed coronary flow reserve (CFR) as a marker of coronary microvascular function in asymptomatic PHPT of recent onset. Methods and Results— We studied 100 PHPT patients (80 women; age, 58±12 years) without cardiovascular disease and 50 control subjects matched for age and sex. CFR in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. CFR was the ratio of hyperemic to resting diastolic flow velocity. CFR was lower in PHPT patients than in control subjects (3.0±0.8 versus 3.8±0.7; P<0.0001) and was abnormal (⩽2.5) in 27 patients (27%) compared with control subjects (4%; P=0.0008). CFR was inversely related to parathyroid hormone (PTH) levels (r=−0.3, P<0.004). In patients with CFR ⩽2.5, PTH was higher (26.4 pmol/L [quartiles 1 and 3, 16 and 37 pmol/L] versus 18 [13–25] pmol/L; P<0.007), whereas calcium levels were similar (2.9±0.1 versus 2.8±0.3 mmol/L; P=0.2). In multivariable linear regression analysis, PTH, age, and heart rate were the only factors associated with CFR (P=0.04, P=0.01, and P=0.006, respectively). In multiple logistic regression analysis, only PTH increased the probability of CFR ⩽2.5 (P=0.03). In all PHPT patients with CFR ⩽2.5, parathyroidectomy normalized CFR (3.3±0.7 versus 2.1±0.5; P<0.0001). Conclusions— PHPT patients have coronary microvascular dysfunction that is completely restored after parathyroidectomy. PTH independently correlates with the coronary microvascular impairment, suggesting a crucial role of the hormone in explaining the increased cardiovascular risk in PHPT.

Impaired coronary flow reserve in young patients affected by severe psoriasis.

OBJECTIVE Our study aimed to evaluate the effects of psoriasis (Pso) on coronary microvascular function and whether there is a relationship between disease activity scores and coronary blood flow abnormalities. METHODS 56 young patients (pts) with Pso (42 M, aged 37±3 years) without clinical evidence of cardiovascular diseases, and 56 controls matched for age and gender were studied. Coronary flow velocity in the left anterior descending coronary artery was detected by transthoracic echocardiography at rest and during adenosine infusion. Coronary flow reserve (CFR) was the ratio of hyperaemic diastolic flow velocity (DFV) to resting DFV. A CFR≤2.5 was considered abnormal. RESULTS In pts with Pso, CFR was lower than in controls (3.2±0.9 vs. 3.7±0.7, p=0.02). CFR was abnormal (≤2.5) in 12 pts (22% vs. 0% controls, p<0.0001). Moreover, in pts with CFR≤2.5, Psoriasis Area Severity Index (PASI), a clinical score for Pso severity, was higher (11±6 vs. 7±3, p=0.006) compared to pts with CFR>2.5. At multivariable analysis PASI remained the only determinant of CFR≤2.5 (p=0.02). CONCLUSION CFR in young pts with severe Pso without coronary disease is reduced suggesting a coronary microvascular dysfunction, independently related to the severity and extension of Pso. This early microvascular impairment might be hypothesized as the consequence of prolonged and sustained systemic inflammation and might explain the increased cardiovascular risk conferred by Pso.

Recent Developments on Coronary Microvasculopathy after Heart Transplantation:A New Target in the Therapy of Cardiac Allograft Vasculopathy

Heart transplantation (HTx) is the treatment of choice for patients with refractory end-stage heart diseases. Although the procedure is considered effective in extending and improving quality of life, the onset of cardiac allograft vasculopathy (CAV) continues to limit the long-term success of HTx. Emerging data indicate that the endothelium plays a significant role in the onset, progression and complication of this multifactorial disease, with both immunologic and nonimmunologic risk factors contributing to its development. Improving our understanding of the integral role of the coronary microcirculation in CAV is of crucial clinical interest since it could provide further insights into the related pathophysiological mechanisms and possible new strategies for CAV prevention and therapy. Assessment of coronary microvasculopathy has been shown to be of predictive value after HTx. Predominant allograft microvascular dysfunction is detectable in 15-20% of patients after HTx. Very recently, stenotic microvasculopathy (detected in biopsy samples) has been characterized as a prognostic factor for long-term survival after HTx. The ability to detect and distinguish changes in epicardial and microvascular function may aid in identifying modifiable factors that lead to CAV. Improved immunosuppressive drugs, including mycophenolate mofetil and proliferation signal inhibitors, as well as statins (in part via immunomodulation), may have a beneficial effect on coronary microcirculation after HTx, although there is still a need to confirm the impact of vasodilators in improving the prognosis of HTx patients. We review the role of coronary microvasculopathy in HTx, its prevention and new potential pharmacological interventions.

Coronary Microvascular Dysfunction Correlates With the New Onset of Cardiac Allograft Vasculopathy in Heart Transplant Patients With Normal Coronary Angiography

Coronary microvascular dysfunction is emerging as a strong predictor of outcome in heart transplantation (HT). We assessed the validity of microvascular dysfunction, defined by means of a reduced coronary flow reserve (CFR), as a factor associated with new onset epicardial cardiac allograft vasculopathy (CAV) or death. We studied 105 patients at 4 ± 1 years post‐HT with a normal coronary angiography (CA). New onset CAV was assessed by CA. CFR was assessed in the left anterior descending (LAD) coronary artery by transthoracic Doppler echocardiography and calculated as the ratio of hyperaemic to basal blood flow velocity. A CFR ≤ 2.5 was considered abnormal. Epicardial CAV onset or death was assessed during a follow‐up of 10 years. New onset CAV was diagnosed in 30 patients (28.6%) (Group A), and the CA was normal in the remaining 75 patients (71.4%) (Group B). Group A had reduced CFR compared with group B (2.4 ± 0.6 vs. 3.2 ± 0.7, p < 0.0001). A CFR ≤ 2.5 was independently associated with a higher probability of new onset CAV (p < 0.0001) and a higher probability of death, regardless of CAV onset (p < 0.01). Microvascular dysfunction is independently associated with the onset of epicardial CAV, and associated with a higher risk of death, regardless of CAV onset.

Coronary microvascular dysfunction due to essential thrombocythemia and policythemia vera: The missing piece in the puzzle of their increased cardiovascular risk?

Myeloproliferative neoplasms are most commonly associated with venous thrombosis. Up to 60% of patients experience a thrombotic event in their lifetimes, including stroke or myocardial infarction. It is unclear whether pathogenetic factors linking essential thrombocythemia (ET) and polycythemia vera (PV) to thrombotic complications do play a role in the risk of coronary artery disease (CAD). We aimed to assess coronary flow reserve (CFR) as a marker of coronary microvascular function in asymptomatic patients with ET and PV. Fifty‐two patients with ET (M/F 13/39, age 61 ± 7 years) and 22 patients with PV (M/F 13/9, age 60.4 ± 13 years) without clinical evidence of heart disease, and 50 controls matched for age and gender were studied. None had CAD. All control subjects were asymptomatic with no history of heart disease. CFR in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. In patients with ET and PV, CFR was lower than in controls (2.9 ± 0.94 and 2.2 ± 0.7 vs. 3.8 ± 0.7, P < 0.004 and P < 0.0001 respectively). The prevalence of CFR ≤ 2.5 was higher in patients with ET (20 cases, 38.5%) and PV (15 cases, 68.2%) compared with controls (4.1%) (P < 0.0001). Severe CFR (CFR < 2) impairment was found in eight patients with ET (15.4%), in nine patients with PV (40.9%), and in none of control subjects. The mutation of JAK2 gene was associated with abnormal CFR. Asymptomatic patients with ET and PV have coronary microvascular dysfunction in the absence of clinical conditions suggesting CAD. Am. J. Hematol. 90:109–113, 2015.

Everolimus Prevents Coronary Microvasculopathy in Heart Transplant Recipients With Normal Coronary Angiograms: An Anatomo-Functional Study

BACKGROUND Coronary allograft vasculopathy (CAV) involves both epicardial vessels and coronary microcirculation. Little is known about the effect of everolimus on coronary microvasculopathy in heart transplantation (HT). The aim of our study was to assess the pathological substrate of coronary flow reserve (CFR) impairment in HT patients and the effect of everolimus on microvascular remodeling and CFR. METHODS We studied 28 HT patients with normal coronary angiograms (25 male, age at HT 54±10 years). Immunosuppressive regimen consisted of cyclosporine and everolimus (10 patients) or mycophenolate mophetil (18 patients). They were evaluated with digital microscopy for morphometric analysis of fibrosis and microvascular remodeling. Coronary flow velocity in the left anterior descending coronary artery was detected using transthoracic Doppler echocardiography at rest and during adenosine infusion. CFR was the ratio of hyperaemic diastolic flow velocity (DFV) to resting DFV. A CFR≤2.5 was considered abnormal and sign of coronary microvascular dysfunction. RESULTS In patients with CFR≤2.5 the thickness of the tunica media of intramyocardial arterioles was greater than in patients with CFR>2.5 (39±2 vs 17±3 μm; P=.02). Microvascular remodeling was significantly higher in patients with CFR≤2.5 (72.7±2.4 vs 50.4±8.4%; P<.007). Capillary density and fibrosis were comparable between groups (157.2±42.4 vs 175.7±42.4 capillaries/mm2; P=.3; and 6.8±5 vs 8.3±4.9%; P=.4, respectively). The thickness of the tunica media of intramyocardial arterioles was lower in patients whose therapy included everolimus (15±2 vs 32±4 μm, P=.03) and CFR was higher (3.2±0.5 vs 2.8±0.9; P=.03). CONCLUSION The pathological substrate of reduced CFR in HT patients seems to be a hypertrophic remodeling of coronary arterioles. Everolimus appears to prevent such microvascular remodeling and preserve coronary flow reserve.

Coronary microvascular dysfunction may be related to IGF-1 in acromegalic patients and can be restored by therapy

BACKGROUND AND AIMS Acromegaly increases the risk of cardiovascular mortality. Data on the cardiovascular risk in asymptomatic acromegaly are limited. In particular, data on coronary microvascular abnormalities are lacking. We assessed coronary flow reserve (CFR) as a marker of coronary microvascular function in asymptomatic acromegaly. METHODS We studied 40 acromegalic patients (23 male, age 52 ± 11 years) without clinical evidence of cardiovascular disease, and 40 control subjects matched for age and sex. Coronary flow velocity in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. CFR was the ratio of hyperaemic to resting diastolic flow velocity. RESULTS CFR was lower in patients than in controls (2.9 ± 0.8 vs. 3.7 ± 0.6, p < 0.0001) and was abnormal (≤2.5) in 13 patients (32.5%) compared with any control subjects (0%) (p < 0.0001). CFR was inversely related to insulin-like growth factor 1 (IGF-1) levels (r = -0.5, p < 0.004). In patients with CFR≤2.5, IGF-1 was higher (756 [381-898] μg/l versus 246 [186-484] μg/l, p < 0.007) whereas growth hormone (GH) levels were similar (6.3 [2.8-13.7] μg/l versus 5 [2.8-8.9] μg/l, p = 0.8). In multivariable linear regression analysis, IGF-1 was independently associated with CFR (p < 0.0001). In multiple logistic regression analysis, IGF-1 independently increased the probability of CFR≤2.5 (p = 0.009). In four patients with active disease (all with CFR<2.5), treatment with somatostatin analogues normalized CFR. However the other four patients with active disease were not responder. CONCLUSIONS Acromegalic patients have coronary microvascular dysfunction that may be restored by therapy with somatostatin analogues. IGF-1 independently correlates with the coronary microvascular impairment, suggesting the pivotal role of this hormone in explaining the increased cardiovascular risk in acromegaly.