Patients with coronary stenosis and a fractional flow reserve of ≥0.75 measured in daily practice at the VU University Medical Center.

Objectives. The aim of this study was to analyse the rate of major adverse clinical events in patients with coronary artery disease and a fractional flow reserve (FFR) of ≥0.75 and deferred for coronary intervention in daily practice. Methods. From 1 January to 31 December 2006, FFR measurement was initiated in 122 patients (5%) out of 2444 patients referred for coronary angiography. In two patients FFR measurement failed and in one patient the FFR value could no longer be traced in the documents. Thus, 119 patients (84 men, 64 years, range 41-85) were included in the evaluation (145 lesions). Major adverse clinical events (death, myocardial infarction, percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG)) and the presence of angina were evaluated at follow-up. Furthermore a cost-effectiveness analysis was performed.Results. In 93 patients (76%) the FFR value was ≥0.75. Seventy of these 93 patients (76%) were treated with medication alone or underwent PCI for a different lesion (medical treatment group). Average duration of follow-up of all 119 patients was 22 months (range 4 days to 30 months). In the medical treatment group seven patients (10%) experienced a major adverse clinical event related to the FFR-evaluated lesion during follow-up. In this study population, the use of FFR measurement is cost-reducing provided that at least 65% of the patients in the medical treatment group has had a PCI with stent implantation when the use of FFR measurement is impossible. In this case, the decision to use PCI with stent implantation is purely based on the angiogram. Conclusions. In patients with a coronary stenosis based on visual assessment and an FFR of ≥0.75 deferral of PCI or CABG is safe in daily clinical practice and saves money. (Neth Heart J 2010;18:402-7.).

Characteristics of the flow velocity-pressure gradient relation in the assessment of stenoses: an in vitro study.

OBJECTIVES: The flow velocity-pressure gradient (v-dp) relation is clinically used to assess coronary stenoses. This in vitro study aimed to investigate the ability to determine the impact of each individual stenosis in the setting of two consecutive stenoses, the effect of variable stenosis reference diameters and the impact of one or two wires in a stenosis, on the v-dp relation. METHODS: The model consisted of a reservoir and different sized tubes and stenoses. Pressure gradient and flow velocity were assessed with a pressure and a Doppler wire. By plotting flow velocity and pressure gradient on an X-Y plot, the v-dp relation was determined. RESULTS: The v-dp relation of a proximal stenosis was not influenced by a distal stenosis. The diameter of the segment where flow velocity was measured influenced the v-dp relation. This could be corrected by substituting flow velocity with volume flow. The presence of one or two wires in a stenosis made the v-dp relation substantially steeper. CONCLUSIONS: The v-dp relation can be used to determine the significance of each individual stenosis in arteries with consecutive stenoses, provided that the distance between the stenoses is large enough. The diameter of the segment where flow velocity is measured and the presence of one or two wires substantially affect the v-dp relation. (Neth Heart J 2008;16:156-62.).

Right ventricular contractility in systemic sclerosis-associated and idiopathic pulmonary arterial hypertension.

Since systemic sclerosis (SSc) also involves the heart, the aim of the present study was to evaluate possible differences in right ventricular (RV) pump function between SSc-associated pulmonary arterial hypertension (PAH; SScPAH) and idiopathic PAH (IPAH). In 13 limited cutaneous SScPAH and 17 IPAH patients, RV pump function was described using the pump function graph, which relates mean RV pressure ((RV)) and stroke volume index (SVI). Differences in pump function result in shift or rotation of the pump function graph. (RV) and SVI were measured using standard catheterisation. The hypothetical isovolumic (RV) ((RV,iso)) was estimated using a single-beat method. The pump function graph was approximated by a parabola: (RV) = (RV,iso)[1-(SVI/SVI(max))(2)], where SVI(max )is the hypothetical maximal SVI at zero (RV), enabling calculation of SVI(max). There were no differences in SVI and SVI(max). Both (RV) and (RV,iso) were significantly lower in SScPAH than in IPAH ((RV) 30.7+/-8.5 versus 41.2+/-9.4 mmHg; (RV,iso) 43.1+/-12.4 versus 53.5+/-10.0 mmHg). Since higher pressures were found at similar SVI, the difference in the pump function graph results from lower contractility in SScPAH than in IPAH. Right ventricular contractility is lower in systemic sclerosis-associated pulmonary arterial hypertension than in idiopathic pulmonary arterial hypertension.

[Diagnosis of pulmonary hypertension: experiences with 187 patients referred to the VU Medical Center]. / Diagnostiek van pulmonale hypertensie: ervaringen bij 187 patiënten verwezen naar het VU Medisch Centrum.

OBJECTIVE: To describe the results of a multidisciplinary diagnostic protocol in patients referred due to suspected pulmonary hypertension. DESIGN: Descriptive. METHOD: In 187 patients who were referred to the VU Medical Centre, Amsterdam, the Netherlands, between May 1998 and February 2003, due to suspected pulmonary hypertension, the diagnosis was established by means of a multidisciplinary diagnostic protocol. The referral and final diagnoses were analysed, as well as the treatment the patients had received. RESULTS: In 56 patients (30%), the application of the protocol lead to a modification of the diagnosis; 16 patients (9%) were found not to have pulmonary hypertension; in 20 of the 89 patients referred with 'primary pulmonary hypertension' (48% of all referrals), an underlying disease was still identified: 6 cases of a connective tissue disease, 5 cases of a chronic thromboembolic process, 5 cases of a condition of the left heart, and 4 cases of an atrial septal defect. CONCLUSION: The diagnosis 'primary pulmonary hypertension' can only be made once all secondary types of the disease have been ruled out. The application of a multidisciplinary diagnostic protocol together with a contribution of specialists with specific expertise can help to adjust the initial diagnosis and sometimes even reject it.

A review of pulmonary arterial hypertension: Part 1. Novel insights and classification.

Pulmonary arterial hypertension (PAH) is a disease characterised by an increased pulmonary artery pressure. The precapillary pulmonary arteries show distinct pathobiological changes, i.e. medial hypertrophy, intimal fibrosis, microthrombi and plexiform lesions. Although the pathogenesis is not completely understood, pulmonary vascular proliferation and remodelling, due to a variety of mediators, is believed to play the pathogenetic key role. Genetic research reveals molecular deformities and gene mutations associated with phenotypic PAH. This article covers novel insights into pathobiology, pathogenesis and genes of PAH, which led to a novel classification system and a diagnostic work-up, emanated from the World Health Organisation Symposium on Pulmonary Hypertension in Venice in June 2003.

A review of pulmonary arterial hypertension: Part 2: Current and expected treatments.

Medical therapy for pulmonary arterial hypertension (PAH) focuses on pulmonary vascular remodelling and smooth muscle cell proliferation. This article covers the drugs which are approved or are in sight and the evidence-based treatment strategies that target the different pathobiological pathways, emanated from the World Health Organisation Symposium on Pulmonary Hypertension in Venice, June 2003. In addition we briefly look at the 'Venice consensus' on surgical treatment. In the past five and a half years more than 360 patients were seen for pulmonary hypertension in the Free University Medical Centre (VUmc). Present-day treatment, research studies and novel treatment strategies in the VUmc will be reviewed. Future treatments will be on the basis of insights into pathobiology, pathogenesis and genes in PAH and should focus on drug combinations, which theoretically target different or similar pathobiological pathways.

LAD-right ventricular fistula complicating PTCA: another case.

Coronary perforation caused by percutaneous transluminal coronary angioplasty (PTCA) occurs rarely and most often leads to communication to the pericardial space. We report a case where PTCA caused a coronary artery rupture and fistulization to the right ventricular outflow tract.

Percutaneous transluminal angioplasty of the left subclavian artery to prevent or treat the coronary-subclavian steal syndrome.

A hemodynamic significant left subclavian artery stenosis or occlusion proximal to the origin of the left internal mammary artery (LIMA) can result in an impaired or reversed flow through the LIMA and the coronary artery to which it has been anastomosed. In this study, we report on our immediate and long-term follow-up results in 31 consecutive patients who underwent percutaneous transluminal coronary angioplasty of the left subclavian artery shortly before or after coronary artery bypass grafting with use of the LIMA.

The development of the retinal projection to the olivary pretectal nucleus in normal and monocularly enucleated hamsters.

The projection to the olivary pretectal nucleus (OPN) from the contralateral eye is observed on the first day after birth and appears adult-like on postnatal day 5. The ipsilateral projection is present at postnatal day 4, and expands to fill the nucleus overlapping the contralateral projection, though never as dense, between days 6 and 8. Then, in normal hamsters, ipsilaterally projecting fibers retract to the ventral side of the OPN by day 10. However, the dense expanded projection in the dorsal OPN ipsilateral to the remaining eye in monocularly enucleated hamsters persists into adulthood.

The development of the retinal projection to the olivary pretectal nucleus in normal and monocularly enucleated hamsters

The projection to the olivary pretectal nucleus (OPN) from the contralateral eyes is observed on the first day after birth and appears adult-like on postnatal day 5. The ipsilaeral projection is present at postnatal day 4, and expands to fill the nucleous overlapping the contralateral projection, though never as dense, between days 6 and 8. Then, in normal hamsters, ipsilaterally projecting fibers retract to the ventral side of the OPN by day 10. However, the dense expanded projection in the dorsal OPN ipsilateral to the remaining eye in monocularly enucleated hamsters persists adulthood