Transhepatic venous approach to permanent pacemaker placement in a patient with limited central venous access.

The end-stage renal disease population poses a challenge for obtaining venous access required for life-saving invasive cardiac procedures. In this case report, we describe an adult patient with end-stage renal disease in whom the hepatic vein was the only available access to implant a single-lead permanent cardiac pacemaker. A 63-year-old male with end-stage renal disease on maintenance hemodialysis and permanent atrial fibrillation/atrial flutter presented with symptomatic bradycardia. Imaging studies revealed all traditional central venous access sites to be occluded/non-accessible. With the assistance of vascular interventional radiology, a trans-hepatic venous catheter was placed. This was then used to place a right ventricular pacing lead with close attention to numerous technical aspects. The procedure was completed successfully with placement of a single-lead permanent cardiac pacemaker.

Side matters: An intriguing case of persistent left superior vena-cava.

Persistent left superior vena cava, usually an incidental finding, is the most common thoracic vein anatomical variation draining into the coronary sinus. Central venous catheter procedures may be complicated secondary to the presence of a persistent left superior vena cava, leading to life-threatening complications such as arrhythmias, cardiogenic shock, and cardiac arrest. We present a case of persistent superior vena cava diagnosed on transthoracic echocardiogram (TTE) in a patient with congestive heart failure. A dilated coronary sinus was identified on TTE, followed by injection of agitated saline into the left antecubital vein resulting in filling of the coronary sinus prior to the right atrium-an indication of persistent left superior vena-cava. This also was confirmed on cardiac computed tomography. Such a diagnosis is critical in patients who may undergo central venous catheter procedures such as our patient's potential requirement for an implantable cardiovertor defibrillator due to severe global left ventricular systolic dysfunction. The presence of a persistent left superior vena cava should always be suspected when the guidewire takes a left-sided downward course towards the right atrium at the level of the coronary sinus. Therefore, special attention should be paid to the imaging work-up prior to central venous catheter procedures.

Relationships between cardiac magnetic resonance imaging abnormalities in the inter-ventricular septum and Selvester QRS scoring criteria for anterior-septal myocardial infarction in patients with right ventricular volume overload.

BACKGROUND: Patients with ostium secundum atrial septal defects (ASDs) were studied to determine the prevalence of Selvester anteroseptal myocardial infarction QRS points, and to test the hypothesis that there is a relationship between these criteria and thinning and/or scarring of the inter-ventricular septum (IVS). METHODS: Demographic, electrocardiographic (ECG), and cardiac magnetic resonance imaging (CMR) data were acquired on 46 patients with a secundum ASD closed percutaneously. Selvester QRS scoring on patient ECGs was performed for areas representing the anteroseptal region of the left ventricle (LV). The IVS to LV free wall thickness ratio was used to assess thinning of the IVS while late gadolinium enhancement (LGE) of the IVS was used for scarring; both using CMR. RESULTS: Twenty-four (52%) patients scored Selvester QRS points in the anteroseptal region with a mean score of 2.6±1.8. The mean IVS/LV free wall thickness ratio at the basal level and mid-ventricular level was 1.1±0.3 and 1.3±0.3, respectively. There was no association of Selvester QRS points with IVS/LV free wall ratio at the basal (p=0.59) or mid-ventricular (p=0.13) levels. The one patient with LGE in the IVS had 4 Selvester anteroseptal QRS points. CONCLUSION: The results of our study demonstrate that in our patient population there is a 52% prevalence of Selvester anteroseptal QRS points which are due to thinning and/or scarring of the IVS in only one patient.

Quantitative estimation of right ventricular hypertrophy using ECG criteria in patients with pulmonary hypertension: A comparison with cardiac MRI.

In patients with pulmonary arterial hypertension (PAH), right ventricular mass (RVM) correlates linearly with pulmonary artery pressure, and decreases with successful treatment. Accurate measurement of RVM currently requires cardiovascular magnetic resonance (CMR) imaging. We therefore tested the relationship between RVM and a simple, 12 lead ECG-derived value, the Butler-Leggett (BL) score. This has previously been validated in patients with RV hypertrophy (RVH) due to mitral stenosis. We also tested the diagnostic accuracy of the BL score in detecting RVH. The Scottish Pulmonary Vascular Unit database was reviewed retrospectively. Twenty-eight patients with PAH were identified, in whom CMR and ECG data had been recorded no more than 28 days apart. All had completed a comprehensive clinical assessment, including right heart catheterization. CMR-derived absolute RVM and RV mass index (RVMI=RV mass/LV mass) were correlated against BL score. The ability of this score to detect RVH was tested using 2 x 2 contingency tables. RVM and RVMI correlated with BL score (r=0.77, P<0.001 and r=0.78, P<0.001, respectively). A BL score >0.7 mV proved a highly specific but insensitive indicator of RVH, based on either absolute RVM (sensitivity 74%, specificity 100%) or a high RVMI (sensitivity 61%, specificity 100%). The BL score, which can be defined using a standard 12-lead ECG, correlates with RVM and RVMI in patients with PAH. A score >0.7 mV was a highly specific but insensitive indicator of RVH in these patients.

Association of ST segment depression >5 min after exercise testing with severity of coronary artery disease.

OBJECTIVE: To determine the association of prolonged ST segment depression after an exercise test with severity of coronary artery disease. METHODS: A cross sectional study of 100 consecutive patients referred to the cardiology laboratory for stress myocardial perfusion imaging (MPI) conducted between April-August 2008. All selected patients were monitored until their ST segment depression was recovered to baseline. ST segment recovery time was categorized into less and more than 5 minutes. Subsequent gated SPECT-MPI was performed and stratified according to severity of perfusion defect. Association was determined between post exercise ST segment depression recovery time (<5 minutes and >5 minutes) and severity of perfusion defect on MPI. RESULTS: The mean age of the patients was 57.12 +/- 9.0 years. The results showed statistically insignificant association (p > 0.05) between ST segment recovery time of <5 minutes and >5 minutes with low, intermediate or high risk MPI. CONCLUSION: Our findings suggest that the commonly used cut-off levels used in literature for prolonged, post exercise ST segment depression (>5 minutes into recovery phase) does not correlate with severity of ischaemia based on MPI results.

The utility of modified Butler-Leggett criteria for right ventricular hypertrophy in detection of clinically significant shunt ratio in ostium secundum-type atrial septal defect in adults.

BACKGROUND: This study was performed to test the hypothesis that there exists a correlation between the Butler-Leggett (BL) criterion for right ventricular hypertrophy on the electrocardiogram and the Qp/Qs shunt ratio in adults with ostium secundum atrial septal defects (ASDs). METHODS: Demographic, cardiac catheterization, ASD closure, and electrocardiographic data were acquired on 70 patients with secundum ASDs closed percutaneously. Simple linear regression and logistic regression models were created to test the hypothesis. RESULTS: The mean Qp/Qs ratio and BL criterion value were 1.61 +/- 0.46 and 0.11 +/- 0.41, respectively. The BL criterion values correlated with shunt ratios (r(2) = 0.11 and P = .004). A BL criterion value greater than 0 mV predicted a significant shunt ratio (Qp/Qs > or = 1.5) (odds ratio, 4.8; 95% confidence interval, 1.3, 18.1; P = or <.0001) with a sensitivity of 0.68 and specificity of 0.65. CONCLUSION: Our results indicate that there is limited utility of the BL criterion at detecting right ventricular volume overload, although a BL criterion value greater than 0 mV being used to identify patients with significant intracardiac shunts yielded a sensitivity of 0.68 and specificity of 0.65.