Clinical articles

The dipeptidyl peptidase-4 (DPP-4) inhibitors are a new class of oral drugs for the treatment of type 2 diabetes. They inhibit the breakdown of glucagon-like peptide-1 (GLP-1) and increase the incretin effect in patients with type 2 diabetes. In clinical practice they are associated with significant reductions in HbA_1c, no weight gain and a low risk of hypoglycaemia. Initial cardiovascular safety studies have shown no increase in cardiovascular risk. Indeed, the suggestion of possible cardiovascular benefit seen in the safety studies is now being formally examined in large randomised-controlled trials with primary cardiovascular end points.

Hyponatraemia has been shown to be an independent predictor of mortality in selected patients with heart failure (HF) enrolled in clinical trials. The predictive value of hyponatraemia has not been evaluated in ambulatory heart failure patients in the community.

We evaluated 426 patients with left ventricular systolic dysfunction and hyponatraemia (between 125 and 135 mmol/L) under the care of a regional nurse-led community heart failure team between June 2007 and November 2008. Of all patients, 92% were on loop diuretics, 81% on angiotensin-converting enzyme (ACE) inhibitors, 90% on beta blockers and 48% on aldosterone antagonists. Mean age of the patients was 78.9 ± 4.7 years, 43% were females and mean New York Heart Association (NYHA) class was 2.3 ± 0.7. Patients were assigned into four groups based on their serum sodium: Group 1 (n=210), 133–135 mmol/L; Group 2 (n=123), 129–132 mmol/L; Group 3 (n=93), 125–128 mmol/L; Group 4 (n=200), >135 mmol/L. Mean follow-up was 12.2 ± 4.9 months. One-year survival was 93% in patients in Groups 1 and 2, 88% in those in Group 3 and 97% in Group 4 (p<0.0001). Risk-adjusted hazard ratios for six and 12-month re-hospitalisations for worsening HF were 2.9 (1.4–3.8) for Group 1 and 2 and 3.6 (1.4–4.2) for Group 3.  

Persistent hyponatraemia is common in ambulatory HF patients in the community and is associated with worse clinical outcomes. It is also an independent predictor for mortality and HF hospitalisations. General practitioners are uniquely positioned to identify patients with hyponatraemia and ensure regular monitoring and appropriate referrals are instigated. 

Mitral valve stenosis (MS) is attributed mainly to rheumatic fever and may remain unrecognised for several years. Early diagnosis of this lesion is important in order to implement the necessary management when either severe or complicated by atrial fibrillation. However, its incidence in a multi-ethnic community has not yet been recognised. We retrospectively studied 2,099 consecutive subjects for the presence of MS. All the patients were newly referred by general practitioners to a community general cardiology clinic and hypertension clinic in a district of London because of different cardiac symptoms, significant cardiac history or because of uncontrolled hypertension. All the patients underwent echocardiography routinely. Classical clinical signs of MS were present in four patients. Echocardiography showed MS in eight patients, in four of whom the MS was mild, moderate in three and severe in one patient. None of the patients had symptoms related to the MS and all were in sinus rhythm both clinically and during Holter monitoring. Only one patient was Caucasian, two were of Caribbean origin and five were of Indo-Asian origin. Subsequent cardiac catheterisation and mitral valve replacement were successfully carried out in two patients. It is concluded that rheumatic MS is still prevalent in the UK population and is more common in subjects of Indo-Asian origin than either Caucasian or Afro-Caribbean subjects. MS was not recognised by the general practitioners: its diagnosis was only made possible by echocardiography. 

Spontaneous coronary artery dissection is a rare entity leading to acute coronary syndrome and sudden cardiac death. Most of these reported cases have occurred in young pregnant women and therapeutic management options are variable. We describe a case of a young patient who presented with ST-elevation myocardial infarction (STEMI) due to coronary artery dissection secondary to cocaine abuse.

Syphilis is a venereal disease that can also be acquired by exposure to infected blood and body fluids. The organism can cross the placenta and infect the unborn child. Untreated syphilis progresses through four stages: primary, secondary, latent, and tertiary stages. Syphilis is a great imitator; patients with syphilis can be a diagnostic challenge because of their wide-ranging clinical presentations. Although the incidence of syphilis has declined dramatically following the advent of penicillin therapy, it is still prevalent due to unsafe sex, multiple sexual partners and intravenous drug abuse. Primary and secondary syphilis can present with minor symptoms while tertiary syphilis can cause mortality in up to 20% of untreated patients due to neurological and cardiovascular complications.

This study aimed to describe adverse events associated with atrial fibrillation (AF), and the medications used to treat it, and to estimate the importance of these adverse events from the perspective of the condition-naïve general public. Fourteen adverse event health state descriptions associated with paroxysmal/persistent and permanent AF were produced based on EQ-5D survey data, a literature review, and qualitative input from patients and clinicians. Further interviews with clinicians and AF patients confirmed the content of the health states as descriptions appropriate to AF. In total, 127 members of the general public valued the health states in a time trade-off interview and ranking task. 

The study revealed how the public view the disutility of adverse health states associated with the treatment of AF. Each of the adverse events was associated with a perceived impairment from their respective base position. Interstitial lung disease showed the greatest perceived impact on quality of life (–0.17 paroxysmal/persistent base; –0.15 permanent base), whereas peripheral vasoconstriction had the least impact (–0.01 paroxysmal/persistent; –0.02 permanent). 

In conclusion, this study provides insight into the importance of treatment-related adverse events in AF. The quality of life estimates collected in this study may prove useful in populating cost-effectiveness analyses and informing clinical treatment decisions.

The role of clopidogrel after percutaneous coronary intervention (PCI) or acute coronary syndrome (ACS) is well supported by strong clinical evidence, which has led to a dramatic increase in its use. 

Enoxaparin is recommended for treatment of patients with acute coronary syndromes (ACS). While plasma monitoring of enoxaparin is not usually required, it may be assessed by measuring plasma anti-Xa levels (therapeutic range 0.5–1.2 IU/ml). Low anti-Xa activity is independently associated with increased 30-day mortality. Although the typical ACS enoxaparin dose is 1 mg/kg twice daily, in clinical practice some treatment protocols dose cap to reduce bleeding risk (for example, some local units cap at 60 mg twice daily).

We studied 20 consecutive patients admitted with ACS. All received enoxaparin 60 mg twice daily. Peak plasma anti-Xa activity was measured four to six hours after the morning dose of enoxaparin after at least two subcutaneous doses. Mean Thrombolysis in Myocardial Infarction (TIMI) risk score 4.2/7 and mean weight 81.9 kg. One third of patients (five male, two female) were found to have subtherapeutic anti-Xa levels (mean 0.35 IU/ml, range 0.2–0.49 IU/ml). The remainder had anti-Xa levels within the therapeutic range (mean 0.73 IU/ml, range 0.5–1.12 IU/ml). Mean weight was higher in those with subtherapeutic compared with therapeutic anti-Xa levels (89.9 vs. 77.6 kg; p=0.041).

In conclusion, dose capping of enoxaparin at 60 mg twice daily in ACS patients may result in a significant proportion achieving subtherapeutic anti-Xa levels, potentially correlating with poorer outcome.

Acarbose is an alpha-glucosidase inhibitor acting in the gastrointestinal tract producing modest reductions in postprandial hyperglycaemia, with negligible risk of hypoglycaemia and weight gain. In a subgroup of the United Kingdom Prospective Diabetes Study (UKPDS), acarbose showed glycaemic benefits irrespective of the type of concomitant therapy. Acarbose was shown to produce a significant reduction in the progression to diabetes in patients with impaired glucose tolerance in the Study to Prevent Non-Insulin-Dependent Diabetes Mellitus (STOP-NIDDM) trial, and in a post-hoc analysis of STOP-NIDDM a reduction in cardiovascular events was observed. Gastrointestinal side effects are the main limiting factor in clinical practice, leading to high rates of non-compliance and discontinuation.

As the proportion of patients above the age of 80 years in the UK is increasing it is likely that in the future cardiac centres will be treating an increasing number of octogenarians as part of their patient population. Despite this, there are little contemporary outcome data in this group of patients who often have complex coronary disease.

We aimed to assess, first, the change in demographics of patients undergoing percutaneous coronary intervention (PCI) over a 9-year period at a tertiary cardiac centre within the UK and, second, whether there has been a change in outcome for these patients in terms of major adverse cardiac and cerebrovascular events (MACCE). A retrospective review of registry data on patients who underwent PCI at our institute from 2000–2008 was undertaken. Patients were divided into three groups according to when they underwent PCI: Group A 2000–2002, Group B 2003–2005 and Group C 2006–2008. Demographic data were collected along with the nature of coronary disease treated and MACCE rates.

There were 3,108 patients in Group A, 4,744 patients in Group B and 3,860 patients in Group C. The use of rotablation increased from Group A (0.4%) to Group C (3.8%) (p<0.01), over-the-wire balloons from Group B (0.8%) to Group C (2.7%) (p<0.01), and microcatheters from Group B (0.1%) to Group C (1.25%) (p<0.01). This was accompanied by a decline in total MACCE rates from Group A (1%) to Group C (0.43%). The proportion of patients >80 years increased from Group A (5.8%) to Group C (12.2%) (p<0.01), and a similar decline in MACCE rates was also observed in this age group from Group A (4%) to group C (0.9%) (p<0.01). 

In conclusion, the proportion of elderly patients requiring PCI is increasing. In this group of patients, PCI appears safe and is associated with declining complication rates.