Works an improved external counter pulsation

Kardiologie.org

A new treatment option may soon be available for patients with refractory angina pectoris and high Lp (a) levels. The use of lipid apheresis has been shown to be effective in a randomized study.

A glimmer of hope for patients with refractory angina and high Lp (a) values. In a randomized study, the symptoms of affected patients decreased significantly through the weekly use of lipid apheresis. This could open up a new therapy option for this difficult-to-treat patient group, the study authors hope from this positive result. New treatment strategies are urgently needed here.

Because with the increasing chances of survival for CHD patients, the number of those who continue to suffer from angina pain despite optimized drug therapy, but interventional or surgical revascularization is no longer an option, is growing. The management of such “refractory angina” is difficult due to the lack of therapeutic options.

So far hardly any therapy options

As non-pharmacological therapy options, the ESC guidelines from 2013 only mention extended external counter-pulsation and techniques for neurostimulation. These procedures have been shown to alleviate the symptoms of affected patients and improve quality of life. Convincing evidence of a reduction in the burden of ischemia and mortality is not yet available.

Transmyocardial or percutaneous myocardial revascularization procedures are not recommended because they would have been found to be ineffective.

Lp (a) often increased in refractory angina

Lipoprotein a - abbreviated as Lp (a) - is a known cardiovascular risk factor, the plasma levels of which are noticeably increased in patients with refractory angina - according to a study in 60% of cases. Lp (a) has thus made itself a target for potential therapeutic interventions in refractory angina. The only problem is that high Lp (a) levels have so far not been reduced in a pharmacologically satisfactory manner. The only option remained to remove the lipoprotein from the blood plasma via apheresis.

With this approach, Tina Khan from Royal Brompton Hospital in London and colleagues has actually achieved a significant improvement in clinical parameters in patients with refractory angina.

Significant improvement in clinical parameters

If the patients underwent lipid apheresis, the myocardial perfusion improved significantly compared to a sham procedure: the perfusion reserve determined in the MRI as the quotient of the blood flow under stress and at rest increased by 0.63. The extent of vascular calcification decreased (wall volume of the carotids decreased by 335 mmᶟ). Physical performance (6-minute walk test) and quality of life also improved significantly.

A total of ten patients with refractory angina and elevated Lp (a) plasma levels (> 500 mg / L) were randomized and blinded to undergo weekly blood washing or sham surgery for three months; afterwards, after a one-month washout phase, there was a cross-over to the other study group.

But lipid apheresis is not specific

According to Arnold von Eckardstein, the scientists working with Khan have brought a new therapeutic option for refractory angina into play with this study, which should be further researched. However, the patient selection does not allow the conclusion that lipid apheresis can specifically reduce the symptoms of patients with refractory angina and high Lp (a) values, the arteriosclerosis researcher who works at the University Hospital in Zurich made clear in an editorial.

It is well known that apheresis not only removes Lp (a) from the blood, but also other lipoproteins containing apoB and triglycerides such as LDL, as well as coagulation and certain inflammatory factors to varying degrees. In other words, in addition to the falling Lp (a) plasma levels, other factors, such as hemodynamic factors, may have contributed to the improvement of the angina symptoms.

In order to be able to justify a specific apheresis indication for such patients, one must first show that the intervention in patients with normal Lp (a) values ​​does not bring about any improvement in symptoms, pointed out von Eckardstein; especially since it is a very costly intervention.

In this context, von Eckardstein considers the PCSK9 inhibitors and antisense oligonucleotides directed against Apo (a) to be a promising medicinal approach, with which the Lp (a) level can be lowered more specifically. He could imagine that these drugs will also be tested as a therapeutic option for refractory angina in the future.