Transradial coronary angiography in patients with contraindications to the femoral approach: an analysis of 500 cases.

The transradial approach to coronary angiography is considered by some to be a route of choice, by others to be a route that should be used only where there are relative contraindications to the femoral approach. We present the largest series to date of patients in whom transradial coronary angiography was undertaken specifically because of contraindications to the femoral approach. Since 1995, patients at this cardiothoracic center have been considered for a transradial approach to coronary angiography if there were relative contraindications to the femoral route. Data from 500 patients was prospectively collected. Patients were aged 66 +/- 9 years; 72% were male. Indications for the radial approach included peripheral vascular disease (305), therapeutic anticoagulation (77), musculoskeletal (59), and morbid obesity (32). Sixty-eight patients (14%) required a radial procedure following a failed femoral approach. Access was right radial 291 (58%), left radial 209 (42%). Eighteen operators were involved, but two operators undertook 355 (71%) of the cases. Catheter gauge was 6 Fr (n = 243; 49%), 5 Fr (219; 43%), and 4 Fr (29; 6%). The procedure was successful in 463 cases [92.6%; 88.2% for nonmajority vs. 94.4% (P < 0.05) for the two majority operators]. Success in males (93.6%) significantly exceeded that in females (90.1%; P < 0.05). In-catheter-laboratory duration was 45 +/- 17 min; fluoroscopy time, 7.5 +/- 6 min; radiation dose, 40 +/- 23 CGy. The procedure was without incident in 408 cases (82%). There were procedural difficulties in 18% of cases, including radial artery spasm (12%) and vasovagal response (5%). The incidence was higher with 6 Fr catheters (23%) than with 5/4 Fr (15%; P < 0.05). Major procedural complications occurred in three cases: brachial artery dissection in one and cardiac arrest in two. Postprocedure major vascular complications numbered three: claudicant pain on handgrip in one, ischemic index finger (with subsequent terminal phalanx amputation due to osteomyelitis) in one, and ischemic hand for 4 hr in one. Patients with contraindications to the femoral approach form a high-risk group. In these patients, transradial cardiac catheterization can be performed successfully and with a low risk of major complications. Minor adverse features remain frequent, occurring in one in five cases, though difficulties are minimized both with increasing operator experience and smaller sheath diameter.

Permanent pacemakers: should straightened atrial leads be repositioned?

The aim of this study was to assess if atrial leads whose "J" configuration has straightened significantly on the postprocedural chest X ray should be repositioned. Between January 1996 and December 1997, 445 patients underwent dual chamber pacemaker implantation at the Papworth Hospital. Postprocedural chest X rays were available in 410 of these. The degree of straightening of the tip of the atrial lead was assessed from the lateral chest X ray and was graded as mild (-10 to +10 degrees from the horizontal), moderate (+10 to +30 degrees), or severe (> or = +30 degrees). Patients were followed with regard to atrial sensing and pacing characteristics, lead displacements, and lead revisions. Fifty-two (12%) patients had some degree of straightening (graded mild, moderate, severe) of the atrial lead on the postprocedure chest X ray (passive fixation in 48, active 4). Of these, 12 patients underwent next day lead repositioning, 5 of whom had abnormalities of pacing and/or sensing parameters. Seven patients therefore underwent repositioning of the atrial lead despite normal pacing parameters in view of lead straightening alone. Of the 12 patients who underwent repositioning, 3 still had lead straightening after the second procedure. The cohort for follow-up consisted of 43 patients (24 [56%] men, age 69 +/- 11 years at the time of implant) who were left with significant atrial lead straightening but adequate atrial parameters. Straightening was mild in 26 patients, moderate in 10, and severe in 7 patients. At implant the P wave amplitude was 4.8 +/- 2.4 mV. Follow-up was for 4.8 +/- 2.1 years, a total of 178 patient years. At final follow-up, the P wave amplitude was 2.7 +/- 1.3 (P < 0.05 vs implant). Censoring events occurred in 16 cases, comprising 11 deaths (none suspected to be pacemaker or lead related), 3 cases of persistent atrial fibrillation, 1 system extraction for infection, and 1 lead extraction for erosion. There were no cases of inadequate atrial lead sensing or pacing in the remaining patients. Irrespective of the degree of lead straightening on the postoperative lateral chest X ray, atrial leads should not be repositioned unless there are abnormalities of pacing or sensing parameters.

Coronary angiography in the fully anticoagulated patient: the transradial route is successful and safe.

The radial approach to coronary angiography is intuitively attractive for fully anticoagulated patients (INR > 2) but no data exist concerning efficacy or safety of this procedure. The consensus view is that the femoral approach is contraindicated in fully anticoagulated patients, and though some operators undertake femoral catheterization in such patients and use closure devices, there are no data to suggest that it is safe to do so. At our institution, the radial approach for coronary angiography is reserved for patients in whom there is a relative contraindication to the femoral route. We have undertaken over 600 radial coronary angiograms in such patients since 1996, 66 of whom underwent transradial catheterization specifically because of anticoagulation status (INR > 2). Thirty-eight patients (58%) were male, average age 67 +/- 11 years. All 66 patients had an INR > 2 but < 4.5. The approach was left radial in 26 (39%), right radial in the remainder; sheath size was 4 Fr in 4 (6%), 5 Fr in 13 (20%), and 6 Fr in 49 (74%). Seven operators in total were involved, though two operators undertook the majority of cases (47; 71%). Success rate was 97%, with no failure of access, and only one minor postprocedural hemorrhage. Failures were due to radial artery atherosclerosis (1) and subclavian tortuosity (1). The radial approach to coronary angiography is safe and to be recommended in the fully anticoagulated patient.

Occasional-operator percutaneous brachial coronary angiography: first, do no arm.

The percutaneous brachial approach to coronary angiography is perceived, rightly or wrongly, to be the easiest of the arm approaches. Predominantly femoral operators may therefore be encouraged to use the percutaneous brachial approach as an occasional procedure. We decided to investigate prospectively whether this was a reasonable strategy by examining outcome in patients who underwent percutaneous brachial cardiac catheterization by occasional brachial operators. Between October 1997 and 2000, 55 patients underwent percutaneous brachial coronary angiography (0.6% of coronary angiographies), aged 66 +/- 10 years, of whom 40 (73%) were male. Chief indications for a brachial approach were peripheral vascular disease in 35 (64%), failed femoral approach in 10 (18%), and orthopnoea in 5 (9%). The procedure was completed successfully in 46 patients (84%). Reasons for failure were failure of access (two), brachial artery spasm (one), inability to negotiate brachial/subclavian tortuosity (two), dissection of the brachial artery (two), and inability to intubate a vein graft (two). Six patients required catheterization from an alternative site (brachial arteriotomy in two, percutaneous transradial in two, femoral in two), with success in all. There were complications of varying severity in 20 patients (36%). Major complications were false aneurysm requiring surgical repair (one), large brachial hematoma requiring surgical exploration and arterial repair (one), and hematoma with clinical median nerve dysfunction for one month. Minor complications included need for repeat coronary angiography via alternative approach (six), weakness of radial pulse < 24 hr (two), brachial artery dissection without clinical sequelae (two), brachial artery spasm terminating procedure (one), and wound oozing (three). Percutaneous brachial coronary angiography is a hazardous procedure when undertaken by occasional brachial operators. Complications are unacceptably frequent. As with all practical procedures, complication rates are likely to be inversely proportional to operator volumes. Patients requiring an arm approach should be referred to operators with high-volume brachial or radial experience.

Cardio-pulmonary responses and gas exchange during exercise in adults with homozygous sickle-cell disease (sickle-cell anaemia)

Cardio-pulmonary responses and gas exchange during progressive exercise, the ventilatory response to hypercapnia and anthropometric indices were measured in twenty-two Jamiacan adults with homozygous sickle-cell disease. Their anthropometric indices and exercise performances were compared with those observed in healthy but sedentary adults in the Caribbean. The patients had long lower limbs for their height; their body fat, proportion of lean body mass as muscle and vital capacity reduced. Haemoglobin concentration ranged from 4 to 10g/100ml. Heart rate and ventilation were normal at rest. During exercise in the male patients haemoglobin concentrations below about 8g/100ml were associated with an increased demand for anaerobic metabolism. This resulted in excessive lac ticacidaemia and increased ventilation at standard oxygen uptake (hyperpnoea). The ventilation-tidal volume relationship was normal. When allowance was made for differences in body muscle, anaemia did not appear to affect the heart-rate response to exercise. Hyperventilation with respect to carbon dioxide output, increased alveolar-arterial oxygen-tension gradients and abnormal deadspace ventilation during exercise indicated a pulmonary perfusion disturbance with mixed venous shunting. The most likely basis for this disorder was considered to be the sickling phenomenon. Arterial hypoxaemia produced by the pulmonary shunt probably accounted for some of the exercise hyperpnoea, partly by increasing the chemoreceptor drive and partly by encouraging lacticacidaemia. Reduced arterial carbon dioxide tensions and bicarbonate concentrations had lowered the threshold and increased the sensitivity of the ventilatory response to carbon dioxide as measured by rebreathing. Increased chemosensitivity was not thought to have contributed towards the exercise hyperpnoea since arterial carbon dioxide tensions were below the threshold value for ventilatory drive. Exertional dyspnoea in sickle-cell disease was attributed to the combination of hyperpnoea and reduced maximum breathing capacity (MBC) owing to small lung volumes. The fraction of (MBC) used at standard work was therfore abnormally large, and the increased ventilatory effort produced a sensation of breathlessness in some patients (Summary)

The in vivo sickle phenomenon: a reappraisal

Previous studies elsewhere have cast doubt on the in vivo relationship between oxygen saturation and red cell sickling. We have reinvestigated this relationship and find the expected correlation to occur at a variety of in vivo sampling sites. The correlation is apparent within data from single individuals, but may be lost when individual susceptibility to sickle cell formation is overlooked by pooling data from different patients. Samples from the hepatic vein did not usually fit the correlation and the unusual factors at this site are discussed (AU)

Clinical features of pulmonary lesions in sickle cell anaemia

Acute pulmonary diseases in patients with sickle cell anaemia are usually diagnosed as pneumonia, but in our experience their rate of resolution and clinical course is different from pneumonia occuring in patients with normal haemoglobins. To confirm this we analysed the clinical course of these clinical episodes in a group of patients with sickle cell anaemia and compared them with a control group of patients with acute lobar pneumonia (AU)