Extending the reach of expert amyloidosis care: A feasibility study exploring the staged implementation of a UK amyloidosis network.

There has been an exponential increase in the diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CA). In response, the Midlands Amyloidosis Service was launched with the aim of providing patients with a timely diagnosis, remote expertise from the National Amyloidosis Centre and access to emerging transthyretin (TTR)-directed therapies. This was a descriptive study of a pilot hub-and-spoke model of delivering specialist amyloidosis care. Patients with suspected amyloidosis were referred from the wider Midlands region, and seen in a consultant-led multidisciplinary clinic. The diagnosis of ATTR-CA was established according to either the validated non-biopsy criteria or histological confirmation of ATTR deposits with imaging evidence of amyloid. Study endpoints were the volume of service provision and the time to diagnosis from the receipt of referral. Patients (n=173, age 75±2 years; male 72 %) were referred between 2019 and 2021. Eighty patients (46 %) were found to have cardiac amyloidosis, of whom 68 (85 %) had ATTR-CA. The median time from referral to diagnosis was 43 days. By removing the need for patients to travel to London, an average of 187 patient-miles was saved. Fifteen (9 %) patients with wild-type ATTR-CA received tafamidis under the Early Access to Medicine scheme; 10 (6 %) were enrolled into phase 3 clinical trials of RNA interference or antisense oligonucleotide therapies. Our results suggest that implementing a UK amyloidosis network appears feasible and would enhance equity of access to specialised amyloidosis healthcare for the increasing numbers of older patients found to have ATTR-CA.

Diagnostic yield of a heart failure referral pathway using N-terminal pro-brain natriuretic peptide.

OBJECTIVE: To determine the diagnostic yield of a 'high' N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with suspected heart failure (HF) referred from primary to secondary care. METHODS: In this retrospective study, cardiac diagnoses were quantified in consecutive patients with an NT-proBNP>400 ng/L referred from primary care centres to a specialist HF service. RESULTS: Among 654 consecutive patients (age: 78.5±9.72 years; 45.9% men; left ventricular ejection fraction (LVEF): 55.4±12.5% (mean±SD)), the primary diagnoses were: valvular disease (39.4%), HF (29.2%; 13.3% with LVEF<40%) and atrial fibrillation (AF; 17.3%). In terms of primary or secondary diagnoses, 68% of patients had valve disease, 46.9% had AF and 29.2% had HF. A cardiac diagnosis was made in 85.9%. In multivariable analyses, NT-proBNP predicted HF with LVEF<40% (OR: 10.2, 95% CI: 5.63 to 18.3) and HF with any LVEF (OR: 6.13, 95% CI: 3.79 to 9.93). In canonical linear discriminant analyses, NT-proBNP correctly identified 54.5% of patients with HF. The remainder were misclassified as valvular disease, AF or no cardiac diagnosis. CONCLUSION: Among patients with an NT-proBNP>400 ng/L referred through a primary care HF pathway, most patients had valve disease or AF rather than HF. NT-proBNP cannot discriminate among HF, valve disease and AF. On this basis, NT-proBNP may be best employed in detecting cardiac disease in general rather than HF per se.

Changing trends in the incidence, management and outcomes of coronary artery perforation over an 11-year period: single-centre experience.

INTRODUCTION: Coronary artery perforation (CP) is a rare but life-threatening complication of percutaneous coronary intervention (PCI). This study aimed to assess the incidence, management and outcomes of CP over time. METHODS: A single-centre retrospective cohort study of all PCIs performed between January 2010 and December 2020. Patients with CP were divided into two cohorts (A+B), representing the two halves of the 11-year study. RESULTS: The incidence of CP was 68 of 9701 (0.7%), with an increasing trend over the two 5.5-year periods studied (24 of 4661 (0.5%) vs 44 of 5040 (0.9%); p=0.035). Factors associated with CP included chronic total occlusions (CTOs) (16 of 68 (24%) vs 993 of 9633 (10%); p<0.001), type C lesions (44 of 68 (65%) vs 4280 of 9633 (44%); p<0.001), use of intravascular ultrasound (IVUS) (12 of 68 (18%) vs 541 of 9633 (6%); p<0.001), cutting balloon angioplasty (3 of 68 (4%) vs 98 of 9633 (1%); p<0.001) and hydrophilic wires (24 of 68 (35%) vs 1454 of 9633 (15%); p<0.001). Cohorts A and B were well matched with respect to age (69±11 vs 70±12 years; p=0.843), sex (males: 13 of 24 (54%) vs 31 of 44 (70%); p=0.179) and renal function (chronic kidney disease: 1 of 24 (4%) vs 4 of 44 (9%); p=0.457). In cohort A, CP was most frequently caused by post-dilatation with non-compliant balloons (10 of 24 (42%); p=0.009); whereas in cohort B, common causes included guidewire exits (23 of 44 (52%)), followed by stent implantation (10 of 44 (23%)). The most common treatment modality in cohorts A and B was balloon inflation, which accounted for 16 of 24 (67%) and 13 of 44 (30%), respectively. The use of covered stents (16%) and coronary coils (18%) during cohort B study period did not impact all-cause mortality, which occurred in 2 of 24 (8%) and 7 of 44 (16%) (p=0.378) in cohorts A and B, respectively. CONCLUSION: The incidence of CP is increasing as more complex PCI is performed. Factors associated with perforation include CTO or type C lesions and use of IVUS, cutting balloon angioplasty or hydrophilic wires.

Contemporary use of excimer laser in percutaneous coronary intervention with indications, procedural characteristics, complications and outcomes in a university teaching hospital.

BACKGROUND: Excimer laser coronary atherectomy (ELCA) can be used as an adjunctive percutaneous coronary intervention treatment for challenging, heavily calcified lesions. Although previous studies have documented high rates of complication and restenosis, these predate the introduction of the smaller 0.9 mm laser catheter. As the coronary complexity has increased, there has been a renewed interest in the ELCA. This study investigates the indications, procedural characteristics, complications and outcomes of ELCA in a contemporary coronary interventional practice. METHODS: This single-centre study retrospectively analysed 50 patients treated with ELCA between January 2013 and January 2019. RESULTS: Patients had a mean age of 67.9±11.4 years with a male predominance (65.3%). 25 (50%) cases were performed in patients with stable angina. Failure to deliver the smallest available balloon/microcatheter was the most frequent indication in 32 (64%) cases for ELCA use. 30 (60%) of the procedures were performed via radial access. The 0.9 mm X-80 catheter was used in 41 (82%) of cases, delivering on average 9000±3929 pulses. ELCA-related complications included 2 coronary dissections and 1 perforation, all of which were covered with stents. No major complications could be directly attributed to the use of ELCA. There was one death and one case of stent thrombosis within 30 days of the procedure. CONCLUSION: ELCA can be performed safely via the radial approach with a 0.9 mm catheter with a high success rate by suitably trained operators. The low procedure-related complications with contemporary techniques make this a very useful tool for complex coronary interventions, especially for difficult to dilate lesions and chronic total occlusion vessels.

How Should We Treat Heavily Calcified Coronary Artery Disease in Contemporary Practice? From Atherectomy to Intravascular Lithotripsy.

Heavily calcified and densely fibrotic coronary lesions continue to represent a challenge for percutaneous coronary intervention (PCI), as they are difficult to dilate, and it is difficult to deliver and implant drug-eluting stents (DES) properly. Poor stent deployment is associated with high rates of periprocedural complications and suboptimal long-term clinical outcomes. Thanks to the introduction of several adjunctive PCI tools, like cutting and scoring balloons, atherectomy devices, and to the novel intravascular lithotripsy technology, the treatment of such lesions has become increasingly feasible, predictable and safe. A step-wise progression of strategies is described for coronary plaque modification, from well-recognised techniques to techniques that should only be considered when standard manoeuvres have proven unsuccessful. We highlight these techniques in the setting of clinical examples how best to apply them through better patient and lesion selection, with the main objective of optimising DES delivery and implantation, and subsequent improved outcomes.

Sodium Nitroprusside in Patients With Mixed Pulmonary Hypertension and Left Heart Disease: Hemodynamic Predictors of Response and Prognostic Implications.

BACKGROUND: Mixed pulmonary hypertension (PH) in heart failure (HF) is defined by transpulmonary gradient ≥ 12 and/or pulmonary vascular resistance (PVR) ≥ 240 dyne/s/cm(-5), but diastolic pressure gradient (DPG) ≥ 7 mmHg has been proposed more recently. We evaluated the acute hemodynamic response to sodium nitroprusside (SNP) specifically in relation to the proposed DPG criterion ≥7 mmHg and the prognostic significance of response to SNP in patients with mixed PH and advanced HF. METHODS: Ninety-eight consecutive patients with advanced HF and mixed PH underwent cardiac catheterization and acute SNP infusion. Baseline hemodynamic parameters included transpulmonary gradient, PVR, DPG, and pulmonary capacitance (PCap). Hemodynamic response to SNP was defined as a reduction in PVR of at least 20%. The composite endpoint was death/heart transplantation/mechanical circulatory support. RESULTS: Sixty of the 98 patients were SNP responders. SNP resulted in significant reductions in filling pressures and PVR and increase in stroke volume and PCap. DPG (not baseline PVR) was significantly associated with hemodynamic response to SNP on logistic regression analysis. The sensitivity and specificity of a DPG ≥7 mmHg to identify nonresponders to SNP were 74% and 97%, respectively. At median follow-up of 218 (148-324) days, 13 and 19 patients of the SNP responders and nonresponders, respectively, met the composite endpoint (P = .021 by log-rank test). Hemodynamic response to SNP and PCap were independently associated with the composite outcome of survival free from transplantation/mechanical circulatory support. CONCLUSION: Baseline DPG ≥ 7 mmHg is associated with poor PVR response to SNP. PVR response to SNP and PCap are associated with a more favorable prognosis in patients with advanced HF and mixed PH.

Percutaneous Mechanical Ventricular Support in Acute Cardiac Care: A UK Quaternary Centre Experience Using 2.5L, 3.8L and 5.0L Impella Catheters.

AIMS: The Impella is a percutaneous ventricular assist device. The majority of published data describes the 2.5L and 5.0L devices, and little data is available for the newer 3.8L device. We examined the indications and outcomes from our single-centre "real-world" registry at The Queen Elizabeth Hospital, Birmingham, UK, using all three pump sizes. METHODS AND RESULTS: Records from all patients who underwent attempted Impella-assisted procedures at our centre were examined retrospectively. Impella implantation was attempted in 49 patients (mean age 72 ± 13 years; 80% male) and was successful in 48 (98%). 45 patients underwent high-risk percutaneous coronary intervention (PCI), one patient underwent balloon aortic valvuloplasty and 3 patients had Impella as a bridge to cardiac transplantation. The 2.5L and 3.8L devices were used in 36 (75%) and 11 (23%) patients, respectively, while one patient (2%) had the 5L device. Vascular complications occurred in only one patient (2%) and stroke and peri-procedural myocardial infarction occurred in one patient (2%), while in-hospital mortality was 20% (10/49). CONCLUSIONS: In this large real-world registry, we have demonstrated the safety and feasibility of the Impella device for a wide range of indications. This includes the first series of the 3.8L device which provides superior support with no increase in vascular complications.

The diagnostic accuracy of plasma BNP and NTproBNP in patients referred from primary care with suspected heart failure: results of the UK natriuretic peptide study.

OBJECTIVES: To determine the diagnostic accuracy of the measurement of plasma B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NTproBNP) in patients referred by their general practitioners (GPs) with symptoms suggestive of heart failure. Additionally, to compare the diagnostic accuracy of the resting 12-lead electrocardiogram (ECG) with that of the peptides. DESIGN: A diagnostic accuracy study. SETTING: Rapid-access heart failure clinics in five hospitals. PARTICIPANTS: 306 patients referred by their GPs with suspected heart failure. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive and negative predictive values (PPV and NPV) and positive and negative likelihood ratios for BNP, NTproBNP and the ECG for the diagnosis of heart failure. Area under the receiver operating characteristics (ROC) curves for the two natriuretic peptides. RESULTS: The diagnosis of heart failure was confirmed in 104 (34%) patients. The area under the ROC curve was 0.84 [95% CI 0.79-0.89] for BNP and 0.85 [0.81-0.90] for NTproBNP. At the manufacturers' recommended decision cut-points, NTproBNP provided a higher NPV (0.97) than BNP (0.87), but at lower PPV (0.44 versus 0.59). An abnormal ECG did not add any further predictive value to that of NTproBNP. CONCLUSIONS: We have confirmed the value of the measurement of plasma BNP or NTproBNP as a 'rule-out' test for heart failure in patients currently referred by GPs to rapid access diagnostic clinics. A simple classification of the 12-lead ECG into 'normal' or 'abnormal' adds little value to ruling out heart failure in these circumstances. Further work is necessary to establish the best decision cut-points for use in clinical practice.