In-stent restenosis is the result of neointimal hyperplasia that, by intravascular ultrasound (IVUS) imaging, typically has a homogeneous, echoreflective appearance.

Percutaneous intervention of coronary ostial stenoses carries a lower procedural success rate and a higher likelihood of acute complication and need for repeat revascularization. Technical challenges related to the treatment of ostial side branches include smaller vessel size, an angulated orientation of the side branch relative to the parent vessel, vascular recoil and plaque shifting into the parent vessel in response to balloon angioplasty. Stents that have been placed in the parent vessel across the origin of side branches confer an additional level of complexity to percutaneous treatment of the side branch. The metal struts of the stent may impede guidewire or balloon access to the “jailed” side branch, and also may limit effective balloon expansion within the side branch. In addition, potential complications of balloon dilatation of side branches through stent struts include device entrapment as well as deformation of the stent struts in the parent vessel.

Aortic stenosis (AS) is commonly encountered by cardiologists. Assessment of AS is routinely performed with Doppler echocardiography, but cardiac catheterization has an important role in the assessment of patients with inconclusive echocardiographic findings. The basis of invasive assessment is the Gorlin equation, which requires measurement of the transvalvular pressure gradient.¹ This gradient can be measured by using the pullback method, but simultaneous assessment of left ventricular pressure and aortic pressure is more accurate.² To obtain simultaneous pressure measurements, most catheterization laboratories use a two-catheter technique that requires two arterial punctures; one catheter is placed in the aorta, and another is placed into the left ventricle using a retrograde approach through the aortic valve.

Bae et al describe the use of a pressure wire in conjunction with a 5–6 Fr guiding catheter to measure transvalvular gradients in 18 patients with aortic stenosis.¹ The method is clearly technically feasible, and correlated well with echocardiographic estimates of aortic valve area. The quality of the pressure tracings using the pressure wire method is excellent, and is reminiscent of the high-fidelity tracings recorded from multisensor electromagnetic tansducer-tipped catheters.

Patent foramen ovale (PFO) is a frequent finding in young patients with cryptogenic stroke.^1–4 PFO has also been related to migraine,5 platypnea-orthodoxia syndrome (condition in which shortness of breath and hypoxemia occur when upright and resolve when prone),6 and decompression illness in divers.⁷ Long-term anticoagulation⁸ and surgical closure of PFO have been used as therapeutic options,^9–12 however, their results have been mixed with respect to stroke prevention. Recently, percutaneous transcatheter PFO closure techniques have been used more frequently as a therapeutic option in these patients.^13–20

In this issue of the Journal of Invasive Cardiology, Alaeddini et al report on the incidence of atrial tachyarrhythmias (AT) in their series of 71 patients who had closure of a patent foramen ovale (PFO) performed for cryptogenic stroke or orthodeoxia.¹ There are many drawbacks to this study, not the least of which is the fact that only patients who complained of palpitations were the ones who were further evaluated by Holter monitoring. In addition, only 48-hour Holter monitoring was performed, rather than longer “event” monitoring, which might have uncovered more AT. Hence, the chances are high that there was significant underreporting of actual AT, as the authors point out.

They point out some important observations from their data:

Recent randomized trials have established that patients who present with acute coronary syndrome (ACS) non-ST-elevation myocardial infarction (MI) may be managed with low-molecular weight heparin (LMWH) followed by early angiography and by appropriate medical management, percutaneous coronary intervention (PCI) or surgery.^1–3 Despite the common utilization of the LMWH enoxaparin for the early treatment of patients presenting with ACS, there is still insufficient information available regarding its efficacy and safety when combined with other antithrombotic agents, such as unfractionated heparin, in the context of an early invasive strategy. This is particularly due to the complexity of switching between subcutaneous and intravenous heparins and the lack of accurate bedside monitoring for anticoagulant levels after administration of a LMWH.

Myocardial infarction with angiographically normal coronary arteries (MINCA) is a well-documented syndrome.¹ The incidence of MINCA among all patients with myocardial infarctions is thought to be low, ranging from 1–5%,^2–4 as reported from older and often incomplete studies. Recent studies^5,6 of patients with MINCA have reported groups, but not the incidence, of patients with an unusual left ventricular wall motion abnormality (LVWMA) called Takotsubo cardiomyopathy,⁷ a rare condition that was first described in Japan and has been documented more recently in the United States.⁸ Takotsubo cardiomyopathy is found predominantly in females. They usually present with chest pain and electrocardiographic (ECG) findings of an acute myocardial infarction in the setting of emotional or physical stress, with elevated cardiac enzymes, normal coronary arteries and a distinctive cardiomyopathy.

Drug-eluting stents (DES) have significantly reduced restenosis. One of the most intensely studied agents considered and currently in clinical use for DES-based local delivery is paclitaxel. Efficacy of paclitaxel-loaded, biostable polymer-coated stents with polymer-based sustained-release, low- and moderate-dose drug delivery for reducing in-stent neointima has been shown in several animal models, including rat, rabbit and pig.^1–5

Several techniques are used to treat coronary bifurcation lesions. One of the commonly used techniques is the jailed wire technique, which is performed by inserting two guidewires into both the main and side branches of a coronary artery. When the main branch is stented, the side branch wire is jailed between the stent and the wall of the proximal main branch. One difficulty with the technique is wire withdrawal. There are no reports in the literature describing a broken jailed wire between two overlapping stents.