A nurse-led palpitations clinic: a 2-year experience.

OBJECTIVE: To investigate the role of a nurse-led clinic in the assessment of patients with palpitations. DESIGN: Prospective descriptive study. SETTING: Nurse-led palpitations clinic in a UK district general hospital. PARTICIPANTS: Patients referred from primary care or the emergency department with palpitations. METHODS: Referral letters were screened, and only patients without high-risk features or a documented arrhythmia were diverted to the palpitations clinic. Patients were evaluated using a protocol. All patients had an ECG and ambulatory ECG monitoring and were discussed with a cardiologist. RESULTS: Over 15 months, 389 patients were seen. The mean time from referral to assessment was 38 days (range 3-142). The most common diagnoses were symptomatic extrasystoles (42%) and sinus rhythm (22%). Significant arrhythmias were diagnosed in 15% (atrial fibrillation/flutter, 8%; supraventricular arrhythmias, 6%). Only 52 (13%) were subsequently referred to a cardiologist, including 20 with high-risk features. These 20 patients waited on average an additional 70 days to be seen by a cardiologist compared with patients who were seen directly by a cardiologist after referral by primary care or the emergency department. CONCLUSIONS: For low-risk patients, a nurse-led palpitations clinic may provide a viable alternative to the traditional cardiology outpatient service. Despite attempts to exclude them, some high-risk patients were seen. This was unforeseen and led to a clinically important delay in their appropriate assessment. Hence, before adopting a nurse-led palpitations service, a rigorous pathway for the early assessment of high-risk patients needs to be agreed.

Strain and stage specific variation in Toxoplasma gondii antigens.

The antigenic profile of virulent (RH, ENT, Martin) and avirulent (RRA, DEG, ME49) Toxoplasma strains was compared directly by western blotting using a panel of immune mouse sera. Dominant antigens of approximate MR 30-33, 21 and 25 x 10(3) were common to tachyzoites of all strains, however, there were significant quantitative and qualitative differences in the antigen profiles, indicating a moderate degree of strain specific polymorphism in tachyzoite antigens. We found no specific association between antigenic variation and strain virulence. Comparison of tachyzoite and bradyzoite antigens from homologous strains (RRA, DEG, ME49) confirmed the existence of stage specific antigens and demonstrated a conserved antigen profile among bradyzoites.

Toxoplasma gondii: the growth characteristics of three virulent strains.

We have studied the phenotype of three mouse virulent strains of Toxoplasma gondii (RH, Martin and ENT), monitoring cellular factors which may relate to virulence. There was variation between these three strains in three separate criteria: invasion, growth and tachyzoite-bradyzoite interconversion. The ENT strain exhibited consistently higher invasion rates, a shorter doubling time and a lower frequency of bradyzoite production than Martin or RH strains. In addition to variation in growth rate, there were also differences in the morphology of the parasites, with the ENT strain exhibiting highly synchronous division giving rise to characteristic rosettes. The Martin strain produced bradyzoites at a higher frequency and, in culture, parasites were often seen in tight clusters, which were reminiscent of early tissue cysts. These phenotypic variations amongst mouse-virulent strains of the parasite may imply underlying genetic differences within the group.